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Background/Objectives: Agility and cognitive abilities are typically assessed separately by different motor and cognitive tests. While many agility tests lack a reactive decision-making component, cognitive assessments are still mainly based on computer-based or paper-pencil tests with low ecological validity. This study is the first to validate the novel SKILLCOURT technology as an integrated assessment tool for agility and cognitive-motor performance.
Methods: Thirty-two healthy adults performed agility (Star Run), reactive agility (Random Star Run) and cognitive-motor (executive function test, 1-back decision making) performance assessments on the SKILLCOURT. Cognitive-motor tests included lower limb responses in a standing position to increase the ecological validity when compared to computer-based tests. Test results were compared to established motor and agility tests (countermovement jump, 10 m linear sprint, T-agility tests) as well as computer-based cognitive assessments (choice-reaction, Go-NoGo, task switching, memory span). Correlation and multiple regression analyses quantified the relation between SKILLCOURT performance and motor and cognitive outcomes.
Results: Star Run and Random Star Run tests were best predicted by linear sprint (r = 0.68, p < 0.001) and T-agility performance (r = 0.77, p < 0.001), respectively. The executive function test performance was well explained by computer-based assessments on choice reaction speed and cognitive flexibility (r = 0.64, p < 0.001). The 1-back test on the SKILLCOURT revealed moderate but significant correlations with the computer-based assessments (r = 0.47, p = 0.007).
Conclusion: The results support the validity of the SKILLCOURT technology for agility and cognitive assessments in more ecologically valid cognitive-motor tasks. This technology provides a promising alternative to existing performance assessment tools.
Objectives: Lumbar spinal stenosis (LSS) and lumbar disc herniation (LDH) are often accompanied by frequently occurring leg cramps severely affecting patients’ life and sleep quality. Recent evidence suggests that neuromuscular electric stimulation (NMES) of cramp-prone muscles may prevent cramps in lumbar disorders.
Materials and Methods: Thirty-two men and women (63 ± 9 years) with LSS and/or LDH suffering from cramps were randomly allocated to four different groups. Unilateral stimulation of the gastrocnemius was applied twice a week over four weeks (3 × 6 × 5 sec stimulation trains at 30 Hz above the individual cramp threshold frequency [CTF]). Three groups received either 85%, 55%, or 25% of their maximum tolerated stimulation intensity, whereas one group only received pseudo-stimulation.
Results: The number of reported leg cramps decreased in the 25% (25 ± 14 to 7 ± 4; p = 0.002), 55% (24 ± 10 to 10 ± 11; p = 0.014) and 85%NMES (23 ± 17 to 1 ± 1; p < 0.001) group, whereas it remained unchanged after pseudo-stimulation (20 ± 32 to 19 ± 33; p > 0.999). In the 25% and 85%NMES group, this improvement was accompanied by an increased CTF (p < 0.001).
Conclusion: Regularly applied NMES of the calf muscles reduces leg cramps in patients with LSS/LDH even at low stimulation intensity.
Highlights
• Investigation of how the peripheral muscle system responds to imagination in interaction with proprioceptive information.
• Motor imagery altered time to contraction but not velocity and maximal displacement of the muscle belly.
• Findings indicate that MI might impact on the initiation of contraction.
Abstract
Many studies have investigated the activation of cortical areas and corticospinal excitability during motor imagery (MI) in relation to motor execution. Similar activation of cortical areas during imagined and executed bodily movements and increased corticospinal excitability while imagining movements has been demonstrated. Despite these similarities on the central nervous system level, there is no overt movement during MI. This suggests that centrally generated signals must be inhibited at some level. Second, even in the absence of movement, some studies find behavioral effects of MI interventions. Most of the studies have investigated the role of MI on the cortical or spinal level, but less is known about the peripheral level, such as the muscle system. Testing muscular excitability during MI will give further hints whether and how low-threshold motor commands during MI reach the muscular system. Furthermore, the extent of the shown effects during imagery depends considerably on type of imagery, available proprioceptive information, and imagery ability. Therefore, this study investigates muscular excitability of the biceps brachii muscle manipulating imagery mode (MI vs. visual imagery) and proprioceptive information (with or without muscle effort). 40 participants were included in the analysis. The mechanical response of the muscle after a single electrical stimulus was assessed via tensiomyography. The corresponding variables maximal displacement, delay time, and contraction velocity were used to calculate 2 × 2 ANOVAs with repeated measurements. The absence of interaction effects shows that possible imagery effects on the muscle system are not increased by effort. MI altered time to contraction with lower delay time compared to control condition. Velocity and maximal displacement of the muscle belly during contraction did not differ between imagery conditions. This indicates that MI might impact on the initiation of muscle contraction but does not change the contraction itself. Thus, neuronal factors are moving further into focus in the context of MI research.
Stabilization exercise (SE) is evident for the management of chronic non-specific low back pain (LBP). The optimal dose-response-relationship for the utmost treatment success is, thus, still unknown. The purpose is to systematically review the dose-response-relationship of stabilisation exercises on pain and disability in patients with chronic non-specific LBP. A systematic review with meta-regression was conducted (Pubmed, Web of Knowledge, Cochrane). Eligibility criteria were RCTs on patients with chronic non-specific LBP, written in English/German and adopting a longitudinal core-specific/stabilising/motor control exercise intervention with at least one outcome for pain intensity and/or disability. Meta-regressions (dependent variable = effect sizes (Cohens d) of the interventions (for pain and for disability), independent variable = training characteristics (duration, frequency, time per session)), and controlled for (low) study quality (PEDro) and (low) sample sizes (n) were conducted to reveal the optimal dose required for therapy success. From the 3,415 studies initially selected, 50 studies (n = 2,786 LBP patients) were included. N = 1,239 patients received SE. Training duration was 7.0 ± 3.3 weeks, training frequency was 3.1 ± 1.8 sessions per week with a mean training time of 44.6 ± 18.0 min per session. The meta-regressions’ mean effect size was d = 1.80 (pain) and d = 1.70 (disability). Total R2 was 0.445 and 0.17. Moderate quality evidence (R2 = 0.231) revealed that a training duration of 20 to 30 min elicited the largest effect (both in pain and disability, logarithmic association). Low quality evidence (R2 = 0.125) revealed that training 3 to 5 times per week led to the largest effect of SE in patients with chronic non-specific LBP (inverted U-shaped association). In patients with non-specific chronic LBP, stabilization exercise with a training frequency of 3 to 5 times per week (Grade C) and a training time of 20 to 30 min per session (Grade A) elicited the largest effect on pain and disability.
Study design: Systematic review. Background and objectives: Preoperative neuromuscular function is predictive for knee function and return to sports (RTS) after reconstruction of the anterior cruciate ligament (ACL). The aim of this review was to examine the potential benefits of prehabilitation on pre-/postoperative objective, self-reported and RTS-specific outcomes. Methods: A systematic search was conducted within three databases. From the 1.071 studies screened, two randomized control trials (RCTs), two control trials (CTs) and two cohort studies (CS) met the inclusion criteria. Methodological quality rating adopted the PEDro- (RCT, CT) or Newcastle-Ottawa-Scale (CS). Results and conclusions: Methodological quality of the included studies was moderate (PEDro score: 6.5 ± 1.7; range 4 to 9). Two studies reported higher increases of the maximal quadriceps torque from baseline to pre-reconstruction: one study in the limb symmetry index (LSI), and one in both legs of the prehabilitation group compared to the controls. At 12-weeks post-reconstruction, one study (from two) indicated that the prehabilitation group had a lesser post-operative decline in the single-leg-hop for distance LSI (clinically meaningful). Similar findings were found in terms of quadriceps strength LSI (one study). At both pre-reconstruction (three studies) and two-year post-surgery (two studies), the prehabilitation groups reached significantly higher self-reported knee function (clinically meaningful) than the controls. RTS tended to be faster (one study). At two years post-surgery, RTS rates (one study) were higher in the prehabilitation groups. The results provide evidence for the relevance of prehabilitation prior to ACL-reconstruction to improve neuromuscular and self-reported knee function as well as RTS. More high quality confirmatory RCTs are warranted.
Background: Physical activity and sleep quality are both major factors for improving one's health. Knowledge on the interactions of sleep quality and the amount of physical activity may be helpful for implementing multimodal health interventions in older adults. Methods: This preliminary cross-sectional study is based on 64 participants [82.1 ± 6.4 years (MD ± SD); 22 male: 42 female]. The amount of physical activity was assessed by means of an accelerometer (MyWellness Key). Self-reported sleep parameters were obtained using the Pittsburgh Sleep Quality Index. The Barthel Index was used for physical disability rating. Bivariate correlations (Spearman's Rho) were used to explore relationships between the amount of physical activity and sleep quality. To analyse differences between categorial subgroups univariate ANOVAs were applied; in cases of significance, these were followed by Tukey-HSD post-hoc analyses. Results: No linear association between physical activity and sleep quality was found (r = 0.119; p > 0.05). In subgroup analyses (n = 41, Barthel Index ≥90 pts, free of pre-existing conditions), physical activity levels differed significantly between groups of different sleep duration (≥7 h; ≥6 to <7 h; ≥5 to <6 h; <5h; p = 0.037). Conclusion: There is no general association between higher activity levels and better sleep quality in the investigated cohort. However, a sleep duration of ≥5 to <6 h, corresponding to 7.6 h bed rest time, was associated with a higher level of physical activity.
Das Konflikterleben von Schiedsrichtern im Amateurfußball : eine empirisch-qualitative Arbeit
(2020)
Bei der Austragung von Amateurfußballspielen nehmen Schiedsrichter die Rolle von Beobachtern ein, die bei Konflikten selbst zu Betroffenen werden können. Dabei treten auch extreme Formen wie Beleidigungen und Diskriminierungen sowie physische und psychische Gewalt auf. Anliegen der Masterthesis „Das Konflikterleben von Schiedsrichtern im Amateurfußball“ ist es, die Wahrnehmung von Schiedsrichtern in Bezug auf Konflikte im Amateurfußball empirisch-qualitativ zu erfassen und bisherige Forschungsansätze zu erweitern. Grundlage der Arbeit bilden vom Autor geführte problemzentrierte Interviews mit hessischen Unparteiischen, deren Auswertung neue Perspektiven im Gewaltdiskurs des Amateurfußballs anbietet.
Anknüpfend an Untersuchungen von Nachwirkungserscheinungen vor allem an der Taenia coli des Meerschweinchens, bei denen Nachdehnung und Relaxation mit einer Hyperbelfunktion beschrieben wurden, gehörte es zu den Zielen dieser Arbeit, Gesetzmäßigkeiten im zeitlichen Verlauf der Nachdehnung bei dem anders strukturierten Uterushorn in verschiedenen Badlösungen zu untersuchen und insbesondere zu prüfen, ob die Hyperbelfunktion auch darauf angewendet werden kann und welche Rückschlüsse auf die funktionelle Struktur möglich sind.
Nach Voruntersuchungen an 30 Uterushörnern, bei denen auch Fragen der Tierwahl und der Standardisierung des Hormoneinflusses untersucht wurden, folgten nach ausführlicher biomathematischer Planung Hauptuntersuchungen an 58 Uterushörnern. Ein weiteres Ziel der Arbeit, eine wesentliche Verbesserung der Datenerfassung, konnte durch Einsatz eines Kurvenfolgers in Verbindung mit einer EDV-Anlage und eigenen Datenerfassungsprogrammen erreicht werden, wobei besonderer Wert darauf gelegt wurde, die Reproduzierbarkeit der Datenerfassung näher zu untersuchen, um die erzielte Genauigkeit, die höher als bei allen vergleichsweise zitierten Arbeiten liegt, nachprüfbarangeben zu können. Die erweiterten Möglichkeiten der Datenerfassung lieferten den Anstoß zum Erkennen von Problemen in der bisher üblichen Form der Datenauswertung, der Wertestandardisierung und der Nachdehnungsdefinition; hierfür konnten Lösungswege erarbeitet werden: u.a. ein EDV-Programm zur iterativen Hyperbelanpassung, Definition neuer Nachdehnungsgrößen und eine Aufgliederung in eine modellunabhängige und eine modellabhängige Auswertung.
Nach einem ausführlichen Überblick Uber die Physiologie glatter Muskulatur unter den Aspekten von Funktion und Struktur sowie einer Auseinandersetzung mit dem Begriff des Modells erfolgte eine zusammenfassende Datenauswertung: eine univariate Mehrwegkovarianzanalyse bestätigte nicht nur die Bedeutung des Faktors „Badlösung”, sondern ermöglichte auch unerwartete Aussagen über Kovariablen und Wechselwirkungen, die in früheren Arbeiten nicht in die Fragestellungen mit einbezogen worden waren; iterative Kurvenanpassungen zeigten die Überlegenheit mehrerer einfacher logarithmischer und exponentieller Funktionen im Vergleich zur Hyperbelfunktion. Außerdem waren Vergleiche zwischen verschieden strukturierten Muskeln und zwei Tierarten möglich.
Aus den gewonnenen Ergebnissen werden einige Schlußfolgerungen gezogen und Deutungen für die funktionelle Struktur des glatten Muskels gegeben.
Die Fußball-Weltmeisterschaft ist ein internationales Sportereignis, an dem dank der Massenmedien die ganze Welt teilhaben kann. Ungeachtet dieser globalen Dimension steht zumindest in den Ländern, die an der WM teilnehmen, die eigene Nation im Mittelpunkt des Interesses. Aus sport- und mediensoziologischer Sicht stellt sich daher die Frage, auf welche Weise in der medialen Berichterstattung die eigene – und kontrastierend dazu auch die gegnerische – Nation thematisiert wird. Dieser Frage sind Studierende des Masterstudiengangs Sozialwissenschaften des Sports an der Goethe-Universität in einem Seminar zur Soziologie des Mediensports nachgegangen. Sie haben dazu das erste WM-Spiel der deutschen Mannschaft gegen Mexiko analysiert.
During dynamic ultrasound assessments, unintended transducer movement over the skin needs to be prevented as it may bias the results. The present study investigated the validity of two methods quantifying transducer motion. An ultrasound transducer was moved on a pre-specified 3 cm distance over the semitendinosus muscle of eleven adults (35.8 ± 9.8 years), stopping briefly at intervals of 0.5 cm. Transducer motion was quantified (1) measuring the 2-D displacement of the shadow produced by reflective tape (RT) attached to the skin and (2) using a marker-based, three-dimensional movement analysis system (MAS). Differences between methods were detected with Wilcoxon tests; associations were checked by means of intraclass correlation coefficients (ICC 3.1) and Bland–Altman plots. Values for RT (r = 0.57, p < 0.001) and MAS (r = 0.19, p = 0.002) were significantly higher than true distances (TD). Strong correlations were found between RT and TD (ICC: 0.98, p < 0.001), MAS and TD (ICC: 0.95, p < 0.001), and MAS and RT (ICC: 0.97, p < 0.001). Bland–Altman plots showed narrow limits of agreement for both RT (−0.49 to 0.13 cm) and MAS (−0.49 to 0.34 cm) versus TD. RT and MAS are valid methods to quantify US transducer movement. In view of its low costs and complexity, RT can particularly be recommended for application in research and clinical practice. View Full-Text
Keywords: ultrasound; reflective tape; transducer movement
The float serve is an effective weapon to impede the attack of the opposing team. Because of its great importance in indoor and beach volleyball, we measured and quantified the float effect. We recorded 24 float serves of 12 top athletes in beach volleyball and indoor volleyball, respectively, and analyzed them using video analysis. We determined the 3D trajectories of the ball flight and developed two measures to describe the size of the float effect, the mean residuals and the anticipation error. Both were derived from regression models. These measures suggest that the float effect is greater in the vertical plane than in the horizontal plane, both for indoor and beach volleyball. Analyses of ball release velocities suggest that a certain ball release velocity is a necessary, but not sufficient, condition for ball floating. A validation of the float measurements with subjective expert ratings showed a correlation with the horizontal deviations. This study provides a new approach to analyze floating in on-court volleyball serves and broadens the knowledge for float effects in sports.
Purpose: Medically recommended training often faces the dilemma that necessary mechanical intensities for muscle adaptations exceed patients' physical capacity. In this regard, blood flow restriction (BFR) training is becoming increasingly popular because it enables gains in muscle mass and strength despite using low-mechanical loads combined with external venous occlusion. Since the underlying mechanisms are still unknown, we applied invasive measurements during exercise with and without BFR to promote physiological understanding and safety of this popular training technique. Methods: In a randomized cross-over design, ten healthy men (28.1 ± 6.5 years) underwent two trials of unilateral biceps curls either with (BFR) and without BFR (CON). For analysis of changes in intravascular pressures, blood gases, oximetry and electrolytes, an arterial and a venous catheter were placed at the exercising arm before exercise. Arterial and venous blood gases and intravascular pressures were analyzed before, during and 5 min after exercise. Results: Intravascular pressures in the arterial and venous system were more increased during exercise with BFR compared to CON (p < 0.001). Furthermore, arterial and venous blood gas analyses revealed a BFR-induced metabolic acidosis (p < 0.05) with increased lactate production (p < 0.05) and associated elevations in [K+], [Ca2+] and [Na+] (p < 0.001). Conclusion: The present study describes for the first time the local physiological changes during BFR training. While BFR causes greater hypertension in the arterial and venous system of the exercising extremity, observed electrolyte shifts corroborate a local metabolic acidosis with concurrent rises in [K+] and [Na+]. Although BFR could be a promising new training concept for medical application, its execution is associated with comprehensive physiological challenges.
Functional circuit training (FCT) has been demonstrated to acutely enhance cognitive performance (CP). However, the moderators of this observation are unknown. This study aimed to elucidate the role of exercise intensity. According to an a priori sample size calculation, n = 24 healthy participants (26 ± 3 years, 13 females), in randomized order, performed a single 15-min bout of FCT with low (20–39% of the heart rate reserve/HRR), moderate (40–59% HRR) or high intensity (maximal effort). Immediately pre- and post-workout, CP was measured by use of the Digit Span test, Stroop test and Trail Making test. Non-parametric data analyses did not reveal significant differences between conditions (p > 0.05) although parameter-free 95% confidence intervals showed pre-post improvements in some outcomes at moderate and high intensity only. The effort level does not seem to be a major effect modifier regarding short-term increases in CP following HCT in young active adults.
Perceptual-cognitive function and unplanned athletic movement task performance: a systematic review
(2020)
The performance of choice-reaction tasks during athletic movement has been demonstrated to evoke unfavorable biomechanics in the lower limb. However, the mechanism of this observation is unknown. We conducted a systematic review examining the association between (1) the biomechanical and functional safety of unplanned sports-related movements (e.g., jumps/runs with a spontaneously indicated landing leg/cutting direction) and (2) markers of perceptual–cognitive function (PCF). A literature search in three databases (PubMed, ScienceDirect and Google Scholar) identified five relevant articles. The study quality, rated by means of a modified Downs and Black checklist, was moderate to high (average: 13/16 points). Four of five papers, in at least one parameter, found either an association of PCF with task safety or significantly reduced task safety in low vs. high PCF performers. However, as (a) the outcomes, populations and statistical methods of the included trials were highly heterogeneous and (b) only two out of five studies had an adequate control condition (pre-planned movement task), the evidence was classified as conflicting. In summary, PCF may represent a factor affecting injury risk and performance during unplanned sports-related movements, but future research strengthening the evidence for this association is warranted.
Die vorliegende Arbeit liefert ein Versatzstück zu grundlagentheoretischen Überlegungen im Themenfeld Gesundheit. Dabei wird der Fokus insbesondere auf wissenschaftstheoretische, -soziologische und sozialpsychologische Reflektionen der gesundheitsbezogenen Diskurslandschaft im wissenschaftlichen Bereich gelegt. Diese werden nach gesellschaftsdiagnostischen Anteilen der Arbeit in reflektierter Art und Weise in einen diskursiven Vorschlag überführt, der wiederum für Gesundheit im universitären Setting wegweisend sein kann.
The deep fascia enveloping the skeletal muscle has been shown to contribute to the mechanics of the locomotor system. However, less is known about the role of the superficial fascia (SF). This study aimed to describe the potential interaction between the Hamstring muscles and the SF. Local movement of the dorsal thigh's soft tissue was imposed making use of myofascial force transmission effects across the knee joint: In eleven healthy individuals (26.8 ± 4.3 years, six males), an isokinetic dynamometer moved the ankle into maximal passive dorsal extension (knee extended). Due to the morphological continuity between the gastrocnemius and the Hamstrings, stretching the calf led to soft tissue displacements in the dorsal thigh. Ultrasound recordings were made to dynamically visualize (a) the semimembranosus muscle and (b) the superficial fascia. Differences in and associations between horizontal movement amplitudes of the two structures, quantified via cross‐correlation analyses, were calculated by means of the Mann–Whitney U test and Kendal's tau test, respectively. Mean horizontal movement was significantly higher in the muscle (5.70 mm) than in the SF (0.72 mm, p < 0.001, r = 0.82). However, a strong correlation between the tissue displacements in both locations was detected (p < 0.001, r = 0.91). Direct mechanical relationship may exist between the SF and the skeletal muscle. Deep pathologies or altered muscle stiffness could thus have long‐term consequences for rather superficial structures and vice versa.
Phenomenological sociology is one of the most recognized approaches for explaining the constitution of social behaviour and the construction of social reality. To this day, phenomenological sociology usually belongs to the tradition of Edmund Husserl's transcendental phenomenology and to Alfred Schütz's mundane phenomenology, thus generally presenting itself as sociology of lifeworld, sociology of everyday life, and sociology of knowledge. In contrast to this, this paper intends to outline an alternative kind of phenomenological sociology that finds its philosophical foundation in Hermann Schmitz's “New Phenomenology”. With regards especially to Schmitz's theory of the felt body (“Leib”) and his theory of situation, the basic principles of Neophenomenological Sociology (NPS) will be introduced. Their main components are (1) felt body and affective involvement as the pre‐personal apriori of sociality, (2) felt‐bodily communication as the basic unit of sociality, and (3) joint situations as the socio‐ontological foundation and empirical manifestation of sociality. With these specific key concepts, NPS proves itself to be a socio‐theoretical approach whose foremost strength is that it can identify and properly analyse the pathic dimensions of social behaviour and social situations that social sciences tend to overlook.
The influence of delayed auditory feedback on action evaluation and execution of real-life action-induced sounds apart from language and music is still poorly understood. Here, we examined how a temporal delay impacted the behavioral evaluation and neural representation of hurdling and tap-dancing actions in a functional magnetic resonance imaging (fMRI) experiment, postulating that effects of delay diverge between the two, as we create action-induced sounds intentionally in tap dancing, but incidentally in hurdling. Based on previous findings, we expected that conditions differ regarding the engagement of the supplementary motor area (SMA), posterior superior temporal gyrus (pSTG), and primary auditory cortex (A1). Participants were videotaped during a 9-week training of hurdling and tap dancing; in the fMRI scanner, they were presented with point-light videos of their own training videos, including the original or the slightly delayed sound, and had to evaluate how well they performed on each single trial. For the undelayed conditions, we replicated A1 attenuation and enhanced pSTG and SMA engagement for tap dancing (intentionally generated sounds) vs. hurdling (incidentally generated sounds). Delayed auditory feedback did not negatively influence behavioral rating scores in general. Blood-oxygen-level-dependent (BOLD) response transiently increased and then adapted to repeated presentation of point-light videos with delayed sound in pSTG. This region also showed a significantly stronger correlation with the SMA under delayed feedback. Notably, SMA activation increased more for delayed feedback in the tap-dancing condition, covarying with higher rating scores. Findings suggest that action evaluation is more strongly based on top–down predictions from SMA when sounds of intentional action are distorted.
Resistance exercise has been demonstrated to improve brain function. However, the optimal workout characteristics are a matter of debate. This randomized, controlled trial aimed to elucidate differences between free-weight (REfree) and machine-based (REmach) training with regard to their ability to acutely enhance cognitive performance (CP). A total of n = 46 healthy individuals (27 ± 4 years, 26 men) performed a 45-min bout of REfree (military press, barbell squat, bench press) or REmach (shoulder press, leg press, chest press). Pre- and post-intervention, CP was examined using the Stroop test, Trail Making Test and Digit Span test. Mann–Whitney U tests did not reveal between-group differences for performance in the Digit Span test, Trail Making test and the color and word conditions of the Stroop test (p > 0.05). However, REfree was superior to REmach in the Stroop color-word condition (+6.3%, p = 0.02, R = 0.35). Additionally, REfree elicited pre-post changes in all parameters except for the Digit Span test and the word condition of the Stroop test while REmach only improved cognitive performance in part A of the Trail Making test. Using free weights seems to be the more effective RE method to acutely improve cognitive function (i.e., inhibitory control). The mechanisms of this finding merit further investigation.
Physical activity counseling in primary health care is regarded as a useful complementary preventive and therapeutic measure and is advocated by leading public health institutions. This integrative review summarizes the available data on physical activity counseling in primary care in Germany. A systematic literature search in various databases (peer reviewed and grey literature) was carried out for quantitative and qualitative studies on physical activity counseling and use of “Exercise on Prescription”. The 25 studies included show a very high methodological diversity and, in some cases, considerable risks of bias, with limited comparability across studies. Counseling was provided in all studies by physicians. They report frequent physical activity counseling, which is partly confirmed and partly refuted by patient data. The use of “Exercise on Prescription” is at a very low level. Information on the frequency of physical activity counseling in Germany varies depending on data source and is sometimes contradictory. Our review provides a synthesis of various perspectives on routine physical activity counseling in primary care in Germany. Future studies using standardized and validated instruments in representative samples are needed to further knowledge on counseling and to be able to establish trends in prevalence. Strengthening the topics of physical activity and health and physical activity counseling in medical curriculum is strongly recommended.
Triathlon is a popular sport for both recreational and competitive athletes. This study investigated the rates and patterns of stress fractures in the German national triathlon squad. We developed a web-based retrospective questionnaire containing questions about the frequency of stress fractures, anatomic localisation and associated risk factors. The survey was conducted as an explorative cross-sectional study. Eighty-six athletes completed the questionnaire. Twenty athletes (23%) sustained at least one stress fracture. All documented stress fractures were located in the lower extremities. Factors associated with a higher risk for stress fractures were female gender, competitive sport prior to triathlon career, Vitamin D or iron deficiency, menstrual disturbances and a high number of annual training hours. Disseminating knowledge among athletes and their professional community in order to raise awareness about early symptoms and relevant risk factors could help to improve prevention and reduce the incidence of stress fractures.
The purpose of this study was to investigate whether a six-week, twice weekly resistance training (4 sets at 30% 1-RM until failure) with practical blood flow restriction (BFR) using 7cm wide cuffs with a twist lock placed below the patella is superior to training without BFR (NoBFR) concerning muscle mass and strength gains in calf muscles.
A two-group (BFR n = 12, mean age 27.33 (7.0) years, training experience 7.3 (7.0) years; NoBFR n = 9, mean age 28.9 (7.4) years, training experience 7.1 (6.6) years) randomized matched pair design based on initial 1-RM was used to assess the effects on structural and functional adaptations in healthy males (Perometer calf volume [CV], gastrocnemius muscle thickness using ultrasound [MT], 7-maximal hopping test for leg stiffness [LS], 1-RM smith machine calf raise [1-RM], and visual analogue scale as a measure of pain intensity [VAS]).
The mean number of repetitions completed per training session across the intervention period was higher in the NoBFR group compared to the BFR group (70 (16) vs. 52 (9), p = 0.002). VAS measured during the first session increased similarly in both groups from first to fourth set (p<0.001). No group effects or time×group interactions were found for CV, MT, LS, and 1-RM. However, there were significant time effects for MT (BFR +0.07 cm; NoBFR +0.04; p = 0.008), and 1-RM (BFR +40 kg; NoBFR +34 kg; p<0.001).
LS and CV remained unchanged through training. VAS in both groups were similar, and BFR and NoBFR were equally effective for increasing 1-RM and MT in trained males. However, BFR was more time efficient, due to lesser repetition per training session.
Aging is a one-way process associated with profound structural and functional changes in the organism. Indeed, the neuromuscular system undergoes a wide remodeling, which involves muscles, fascia, and the central and peripheral nervous systems. As a result, intrinsic features of tissues, as well as their functional and structural coupling, are affected and a decline in overall physical performance occurs. Evidence from the scientific literature demonstrates that senescence is associated with increased stiffness and reduced elasticity of fascia, as well as loss of skeletal muscle mass, strength, and regenerative potential. The interaction between muscular and fascial structures is also weakened. As for the nervous system, aging leads to motor cortex atrophy, reduced motor cortical excitability, and plasticity, thus leading to accumulation of denervated muscle fibers. As a result, the magnitude of force generated by the neuromuscular apparatus, its transmission along the myofascial chain, joint mobility, and movement coordination are impaired. In this review, we summarize the evidence about the deleterious effect of aging on skeletal muscle, fascial tissue, and the nervous system. In particular, we address the structural and functional changes occurring within and between these tissues and discuss the effect of inflammation in aging. From the clinical perspective, this article outlines promising approaches for analyzing the composition and the viscoelastic properties of skeletal muscle, such as ultrasonography and elastography, which could be applied for a better understanding of musculoskeletal modifications occurring with aging. Moreover, we describe the use of tissue manipulation techniques, such as massage, traction, mobilization as well as acupuncture, dry needling, and nerve block, to enhance fascial repair.
Introduction: The worldwide spread of the novel coronavirus (SARS-CoV2) has prompted numerous countries to restrict public life. Related measures, such as limits on social gatherings, business closures, or lockdowns, are expected to considerably reduce the individual opportunities to move outside the home. As physical activity (PA) and sport participation significantly contribute to health, this study has two objectives. The objectives of this study are to assess changes in PA and well-being since the coronavirus outbreak in affected countries. Additionally, we will evaluate the impact of digital home-based exercise programs on PA as well as physical and mental health outcomes.
Method: A multinational network trial will be conducted with three planned phases (A, B, and C). Part A consists of administering a structured survey. It investigates changes in PA levels and health during the coronavirus outbreak and measures the preferences of the participants regarding online training programs. Part B is a two-armed randomized-controlled trial. Participants assigned to the intervention group (IG) will complete a digital 4-week home exercise training (live streaming via internet) guided by the survey results on content and time of program. The control group (CG) will not receive the program. Part C is 4-week access of both CG and IG to a digital archive of pre-recorded workouts from Part B. Similar to Part A, questionnaires will be used in both Part B and C to estimate the effects of exercise on measures of mental and physical health.
Results and Discussion: The ASAP project will provide valuable insights into the importance of PA during a global pandemic. Our initial survey is the first to determine how governmental confinement measures impact bodily and mental well-being. Based on the results, the intervention studies will be unique to address health problems potentially arising from losses in PA. If proven effective, the newly developed telehealth programs could become a significant and easy-to-distribute factor in combating PA decreases. Results of the study may hence guide policy makers on methods to maintain PA and health when being forced to restrict public life.
Study Register: DRKS00021273.
A central motivation for the development of x-ray free-electron lasers has been the prospect of time-resolved single-molecule imaging with atomic resolution. Here, we show that x-ray photoelectron diffraction—where a photoelectron emitted after x-ray absorption illuminates the molecular structure from within—can be used to image the increase of the internuclear distance during the x-ray-induced fragmentation of an O2 molecule. By measuring the molecular-frame photoelectron emission patterns for a two-photon sequential K-shell ionization in coincidence with the fragment ions, and by sorting the data as a function of the measured kinetic energy release, we can resolve the elongation of the molecular bond by approximately 1.2 a.u. within the duration of the x-ray pulse. The experiment paves the road toward time-resolved pump-probe photoelectron diffraction imaging at high-repetition-rate x-ray free-electron lasers.
Current evidence indicates that acute aerobic exercise might increase domain-specific cognitive performance. However, only a small number of studies deduced the impact on lower and higher cognitive functions systematically or analyzed dose–response relationships and the underlying mechanisms. This study aimed to expose the dose–response relationships by investigating the influence of exercise duration on subjective and objective arousal, cognitive attention and visual recognition memory tasks. Nineteen participants (eight female; 25.69 ± 3.11 years) were included in a randomized, three-armed intervention study in a cross-over design. The participants completed three different interventions consisting of either 15, 30 or 45 min of cycling at 60–70% VO2max. Arousal and cognitive measurements were taken before and immediately after (<2 min) exercise. All three interventions led to significant but comparable effects on self-perceived arousal, heart rate (HR) and rating of perceived exertion (RPE) (p < 0.05). Analysis of variance (ANOVA) indicated significant effects of exercise duration on visual recognition memory accuracy. Reaction times for higher and lower cognitive tasks did not change after exercise. Fifteen minutes of aerobic exercise was feasible to induce beneficial changes in self-perceived arousal. Processing speed of visual recognition memory and attention remained unaltered. Exercise exceeding fifteen minutes seemed to negatively impact visual recognition memory accuracy.
Background: The back pain screening tool Risk-Prevention-Index Social (RPI-S) identifies the individual psychosocial risk for low back pain chronification and supports the allocation of patients at risk in additional multidisciplinary treatments. The study objectives were to evaluate (1) the prognostic validity of the RPI-S for a 6-month time frame and (2) the clinical benefit of the RPI-S. Methods: In a multicenter single-blind 3-armed randomized controlled trial, n = 660 persons (age 18-65 years) were randomly assigned to a twelve-week uni- or multidisciplinary exercise intervention or control group. Psychosocial risk was assessed by the RPI-S domain social environment (RPI-SSE) and the outcome pain by the Chronic Pain Grade Questionnaire (baseline M1, 12-weeks M4, 24-weeks M5). Prognostic validity was quantified by the root mean squared error (RMSE) within the control group. The clinical benefit of RPI-SSE was calculated by repeated measures ANOVA in intervention groups. Results: A subsample of n = 274 participants (mean = 38.0 years, SD 13.1) was analyzed, of which 30% were classified at risk in their psychosocial profile. The half-year prognostic validity was good (RMSE for disability of 9.04 at M4 and of 9.73 at M5; RMSE for pain intensity of 12.45 at M4 and of 14.49 at M5). People at risk showed significantly stronger reduction in pain disability and intensity at M4/M5, if participating in a multidisciplinary exercise treatment. Subjects at no risk showed a smaller reduction in pain disability in both interventions and no group differences for pain intensity. Regarding disability due to pain, around 41% of the sample would gain an unfitted treatment without the back pain screening. Conclusion: The RPI-SSE prognostic validity demonstrated good applicability and a clinical benefit confirmed by a clear advantage of an individualized treatment possibility.
Knee acoustic emissions provide information about joint health and loading in motion. As the reproducibility of knee acoustic emissions by vibroarthrography is yet unknown, we evaluated the intrasession and interday reliability of knee joint sounds. In 19 volunteers (25.6 ± 2.0 years, 11 female), knee joint sounds were recorded by two acoustic sensors (16,000 Hz; medial tibial plateau, patella). All participants performed four sets standing up/sitting down (five repetitions each). For measuring intrasession reliability, we used a washout phase of 30 min between the first three sets, and for interday reliability we used a washout phase of one week between sets 3 and 4. The mean amplitude (dB) and median power frequency (Hz, MPF) were analyzed for each set. Intraclass correlation coefficients (ICCs (2,1)), standard errors of measurement (SEMs), and coefficients of variability (CVs) were calculated. The intrasession ICCs ranged from 0.85 to 0.95 (tibia) and from 0.73 to 0.87 (patella). The corresponding SEMs for the amplitude were ≤1.44 dB (tibia) and ≤2.38 dB (patella); for the MPF, SEMs were ≤13.78 Hz (tibia) and ≤14.47 Hz (patella). The intrasession CVs were ≤0.06 (tibia) and ≤0.07 (patella) (p < 0.05). The interday ICCs ranged from 0.24 to 0.33 (tibia) and from 0 to 0.82 (patella) for both the MPF and amplitude. The interday SEMs were ≤4.39 dB (tibia) and ≤6.85 dB (patella) for the amplitude and ≤35.39 Hz (tibia) and ≤15.64 Hz (patella) for the MPF. The CVs were ≤0.14 (tibia) and ≤0.08 (patella). Knee joint sounds were highly repeatable within a single session but yielded inconsistent results for the interday reliability.
Competition anxiety has been demonstrated to decrease sports performance while increasing burnout risk. To date, its degree in CrossFit (CF) is unknown. The present study, therefore, examines competition fear and relevant coping skills as well as potential correlates of both in individuals participating in CF events. A total of n = 79 athletes answered a battery of three questionnaires (competition fear index, athletic coping skills inventory, mindfulness attention awareness scale). Substantial levels of anxiety, particularly regarding the somatic dimension of the competition fear index, were reported. The most pronounced coping skill was freedom of worry. While age or level of competition showed no/very small associations with survey data, sex was correlated to the psychological characteristics: women reported higher competition fears and lower coping skill levels (p > 0.05). Competition fears are highly prevalent in CF athletes and the preventive value of population-specific interventions, particularly in females, should be investigated in future trials.
Experiments in cadavers have demonstrated significant mechanical interactions between constituents of myofascial chains. However, evidence for such force transmission effects is scarce under in vivo conditions. The purpose of this trial was to examine the impact of ankle motion on soft tissue displacement of the dorsal thigh. Eleven healthy active individuals (26.8 ± 4.3 years, six males), in prone position and with the knee extended, underwent passive calf stretches (ankle dorsal extension) imposed by an isokinetic dynamometer. High-resolution ultrasound was used to simultaneously capture the displacement of the semimembranosus muscle, which was quantified by means of cross-correlation analysis. Inactivity of the leg muscles was controlled using surface electromyography (EMG). One participant had to be excluded due to major EMG activity during the experiment. According to a one-sample t test testing the difference to the neutral zero position, ankle dorsal extension induced substantial caudal muscle displacements (5.76 ± 2.67 mm, p < 0.0001). Correlation analysis (Spearman), furthermore, revealed a strong association between maximal dorsal extension and semimembranosus motion (rho = 0.76, p = 0.02). In conclusion, the present trial provides initial in vivo evidence for a mechanical force transmission between serially connected skeletal muscles. This means that local alterations of the mechanical tissue properties may modify flexibility in neighboring (superior or inferior) joints.
Background: The vascular effects of training under blood flow restriction (BFR) in healthy persons can serve as a model for the exercise mechanism in lower extremity arterial disease (LEAD) patients. Both mechanisms are, inter alia, characterized by lower blood flow in the lower limbs. We aimed to describe and compare the underlying mechanism of exercise-induced effects of disease- and external application-BFR methods. Methods: We completed a narrative focus review after systematic literature research. We included only studies on healthy participants or those with LEAD. Both male and female adults were considered eligible. The target intervention was exercise with a reduced blood flow due to disease or external application. Results: We identified 416 publications. After the application of inclusion and exclusion criteria, 39 manuscripts were included in the vascular adaption part. Major mechanisms involving exercise-mediated benefits in treating LEAD included: inflammatory processes suppression, proinflammatory immune cells, improvement of endothelial function, remodeling of skeletal muscle, and additional vascularization (arteriogenesis). Mechanisms resulting from external BFR application included: increased release of anabolic growth factors, stimulated muscle protein synthesis, higher concentrations of heat shock proteins and nitric oxide synthase, lower levels in myostatin, and stimulation of S6K1. Conclusions: A main difference between the two comparators is the venous blood return, which is restricted in BFR but not in LEAD. Major similarities include the overall ischemic situation, the changes in microRNA (miRNA) expression, and the increased production of NOS with their associated arteriogenesis after training with BFR.
Background: The effects of blood flow restriction (training) may serve as a model of peripheral artery disease. In both conditions, circulating micro RNAs (miRNAs) are suggested to play a crucial role during exercise-induced arteriogenesis. We aimed to determine whether the profile of circulating miRNAs is altered after acute resistance training during blood flow restriction (BFR) as compared with unrestricted low- and high-volume training, and we hypothesized that miRNA that are relevant for arteriogenesis are affected after resistance training.
Methods: Eighteen healthy volunteers (aged 25 ± 2 years) were enrolled in this three-arm, randomized-balanced crossover study. The arms were single bouts of leg flexion/extension resistance training at (1) 70% of the individual single-repetition maximum (1RM), (2) at 30% of the 1RM, and (3) at 30% of the 1RM with BFR (artificially applied by a cuff at 300 mm Hg). Before the first exercise intervention, the individual 1RM (N) and the blood flow velocity (m/s) used to validate the BFR application were determined. During each training intervention, load-associated outcomes (fatigue, heart rate, and exhaustion) were monitored. Acute effects (circulating miRNAs, lactate) were determined using pre-and post-intervention measurements.
Results: All training interventions increased lactate concentration and heart rate (p < 0.001). The high-intensity intervention (HI) resulted in a higher lactate concentration than both lower-intensity training protocols with BFR (LI-BFR) and without (LI) (LI, p = 0.003; 30% LI-BFR, p = 0.008). The level of miR-143-3p was down-regulated by LI-BFR, and miR-139-5p, miR-143-3p, miR-195-5p, miR-197-3p, miR-30a-5p, and miR-10b-5p were up-regulated after HI. The lactate concentration and miR-143-3p expression showed a significant positive linear correlation (p = 0.009, r = 0.52). A partial correlation (intervention partialized) showed a systematic impact of the type of training (LI-BFR vs. HI) on the association (r = 0.35 remaining after partialization of training type).
Conclusions: The strong effects of LI-BFR and HI on lactate- and arteriogenesis-associated miRNA-143-3p in young and healthy athletes are consistent with an important role of this particular miRNA in metabolic processes during (here) artificial blood flow restriction. BFR may be able to mimic the occlusion of a larger artery which leads to increased collateral flow, and it may therefore serve as an external stimulus of arteriogenesis.
When sports are part of a person’s profession or education, their careers are often handicapped by pain, a complex physical and mental state that may already occur at lower career stages. This study was designed to assess the occurrence of pain among sports students and the prevalence of relevant contributing psychosocial co-factors. Exploratory cross-sectional study surveying students at 89 sports faculties of universities in the DACH region using the German Sports Pain Questionnaire. It includes several validated surveys related to pain occurrence in different body regions, injuries, pain diagnoses and pain intensity, depression, anxiety, stress, self-compassion, analgesic and alcohol consumption, as well as sleep quality, health-related quality of life and impairments of quality of life by pain. A total of 865 sports students gave consent to participate in the study, and 664 participants (78%; 23.3 ± 2.84 years, 60% female, 40% male) completed the full survey. More than half of the students (53%; n = 403) showed current pain in 2-5 regions of the body, while subjective pain tolerance was enhanced. General injuries or accidents, medically and self-diagnosed pain diagnoses during the last eight weeks were reported by 30%. A current pain intensity ≥ 3 NRS was prevalent in 28% (n = 205), which correlated with increased pain-related biopsychosocial scores. Sports students had increased scores for depression, anxiety and stress, and self-compassion was reduced (compared to age-controlled national reference data, sports students head increased scores). The mean weekly training workload was 5-7 hours. Analgesics and alcohol consumption was increased, 61% reported insomnia. Across sports students, pain and biopsychosocial burden seem significantly increased when compared to other students and age-controlled cohorts. The data implies the need of giving greater importance to pain management at least from the time of sports studies in order to prevent pain and health risks in sports.
Background: The fascia has been demonstrated to represent a potential force transmitter intimately connected to the underlying skeletal muscle. Sports-related soft tissue strains may therefore result in damage to both structures.
Purpose: To elucidate the prevalence of connective tissue lesions in muscle strain injury and their potential impact on return-to-play (RTP) duration.
Study Design: Systematic review; Level of evidence, 3.
Methods: Imaging studies describing frequency, location, and extent of soft tissue lesions in lower limb muscle strain injuries were identified by 2 independent investigators. Weighted proportions (random effects) were pooled for the occurrence of (1) myofascial or fascial lesions, (2) myotendinous lesions, and (3) purely muscular lesions. Study quality was evaluated by means of an adapted Downs and Black checklist, which evaluates reporting, risk of bias, and external validity.
Results: A total of 16 studies (fair to good methodological quality) were identified. Prevalence of strain injury on imaging studies was 32.1% (95% CI, 24.2%-40.4%) for myofascial lesions, 68.4% (95% CI, 59.6%-76.6%) for myotendinous lesions, and 12.7% (95% CI, 3.0%-27.7%) for isolated muscular lesions. Evidence regarding associations between fascial damage and RTP duration was mixed.
Conclusion: Lesions of the collagenous connective tissue, namely the fascia and the tendinous junction, are highly prevalent in athletic muscle strain injuries. However, at present, their impact on RTP duration is unclear and requires further investigation.
Background: WATSU (portmanteau word: water and shiatsu) is a form of passive hydrotherapy in chest-deep thermoneutral water (35°C = 95°F = 308.15 K). It combines elements of myofascial stretching, joint mobilization, massage, and shiatsu and is reported to be used to address physical and mental issues. The objective of this systematic review (PROSPERO Registration No. CRD42016029347) and the meta-analyses was to assess the applications, indications, and the effects of WATSU to form a basis for further studies.
Methods: A search for "WATSU OR watershiatsu OR (water AND shiatsu)" was conducted without any restrictions in 32 databases. Peer reviewed original articles addressing WATSU as a stand-alone hydrotherapy were assessed for risk of bias. Quantitative data of effects on pain, physical function, and mental issues were processed in random model meta-analyses with subgroup analyses by study design. Effect sizes were expressed as Hedges's g (± 95% confidence intervals).
Results: Of 1,906 unique citations, 27 articles regardless of study design were assessed for risk of bias. WATSU has been applied to individuals of all ages. Indications covered acute (e.g. pregnancy related low back pain) and chronic conditions (e.g. cerebral palsy) with beneficial effects of WATSU regarding e.g. relaxation or sleep quality. Meta-analyses suggest beneficial effect sizes of WATSU on pain (overall Hedges’s g = -0.71, 95% CI = -0.91 to -0.51), physical function (overall Hedges’s g = -0.76, 95% CI = -1.08 to -0.44), and mental issues (overall Hedges’s g = -0.68, 95% CI = -1.02 to -0.35).
Conclusion: Various applications, indications and beneficial effects of WATSU were identified. The grade of this evidence is estimated to be low to moderate at the best. To strengthen the findings of this study, high-quality RCTs are needed.
Die Erfahrung, "…dass alles auch ganz anders sein könnte" ist die wohl wichtigste Erfahrung in Bildungsprozessen. Die Entdeckung von Möglichkeiten, Perspektivwechseln und transformatorischen Selbst-Bildungsprozessen ist zentral für eine gelungene kulturelle Bildungssituation. (Birgit Mandel, 2005).
Die Hessischen Schülerakademien zur Förderung besonders engagierter und begabter junger Menschen wurden bewusst als ein Unterfangen des Forschenden Lernens gegründet und fühlen sich diesem Leitgedanken im Kontext kultureller Bildung verpflichtet. Dieser Satz klingt zunächst einmal gut und zeitgemäß. Doch was steckt genau dahinter?