Sports Medicine

Correction to: Pulmonary and Respiratory Muscle Function in Response to Marathon and Ultra-Marathon Running: A Review On page 8, in the left-hand column, third paragraph, lines 9–13 which previously read:

Comment on: “Revised Approach to the Role of Fatigue in Anterior Cruciate Ligament Injury Prevention: A Systematic Review with Meta-analyses”

Reply to Koller and Schobersberger: Comment on: “Revised Approach to the Role of Fatigue in Anterior Cruciate Ligament Injury Prevention: A Systematic Review with Meta‐analyses”

Exercise Recommendations for Women with Polycystic Ovary Syndrome: Is the Evidence Enough? Abstract In this opinion piece, we summarize, discuss implications of implementation, and critically evaluate our 2018 evidence-based guideline recommendations for exercise and physical activity in women with polycystic ovary syndrome (PCOS). We developed recommendations as part of a larger international guideline development project. The overall guideline scope and priorities were informed by extensive health professional and consumer engagement. The lifestyle guideline development group responsible for the exercise recommendations included experts in endocrinology, exercise physiology, gynecology, dietetics, and obstetrics, alongside consumers. Extensive online communications and two face-to-face meetings addressed five prioritized clinical questions related to lifestyle, including the role of exercise as therapy for women with PCOS. The guideline recommendations were formulated based on one narrative and two evidence-based reviews, before consensus voting within the guideline panel. The development process was in accordance with the Appraisal of Guidelines for Research and Evaluation (AGREE) II, and used the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) framework to assess evidence quality, desirable and undesirable consequences, feasibility, acceptability, cost, implementation, and recommendation strength. Given the evidence for exercise as therapy in PCOS being of low quality, a consensus recommendation was made based on current exercise guidelines for the general population. Women with PCOS and clinicians are forced to adopt generic approaches when recommending exercise therapy that perpetuates clinical management with pharmacological solutions. The current status of evidence highlights the need for greater international co-operation between researchers and funding agencies to address key clinical knowledge gaps around exercise therapy in PCOS to generate evidence for appropriate, scalable, and sustainable best practice approaches.

The Mediating Effect of Pupils’ Physical Fitness on the Relationship Between Family Socioeconomic Status and Academic Achievement in a Danish School Cohort Abstract Introduction Family socioeconomic status influences pupils’ academic achievements, and studies have established positive associations between physical fitness and academic achievements. However, whether physical fitness mediates the relationship remains unknown. Objective We investigated if pupils’ physical fitness mediates the pathway between family socioeconomic status and academic achievement using causal inference-based mediation analysis. Methods This study included 527 girls and 552 boys between 13 and 15 years of age from the Danish municipality of Aalborg. Physical fitness was measured through VO2max tests in 2010 and demographic data were obtained from nationwide registers. Family socioeconomic status was classified into four levels ranging from 1 to 4, where level 1 represents the lowest and level 4 the highest based on either family income or education. Results Controlling for sex, ethnicity, age, and parents’ cohabitation status, all total effects display higher academic achievement with increased family socioeconomic status. Splitting the effects, the direct effects reveal the existence of other pathways not involving physical fitness. The indirect effects established physical fitness as a mediator showing that pupils from family socioeconomic status levels one, three, and four changes grade by − 0.13 [95% confidence interval (CI) − 0.26, − 0.01], 0.07 (95% CI 0.00, 0.14), and 0.24 (95% CI 0.14, 0.34), respectively, compared to socioeconomic status level two. The corresponding proportions mediated are 18% (95% CI 1, 57), 6% (95 CI 0, 13), and 12% (95% CI 7, 18) when family socioeconomic status is based on education. Classifying family socioeconomic status on income, pupils from family socioeconomic status levels one, three, and four show grade changes of − 0.07 (95% CI − 0.16, 0.02), 0.22 (95% CI 0.13, 0.32), and 0.26 (95% CI 0.15, 0.37), respectively, compared to socioeconomic status level two. The corresponding proportions mediated are 12% (95% CI − 6, 41), 30% (95% CI 16, 54), and 20% (95% CI 12, 32). Conclusion In conclusion, pupils’ physical fitness partially mediated the pathway between family socioeconomic status and academic achievement.

Physical Activity Intolerance and Cardiorespiratory Dysfunction in Patients with Moderate-to-Severe Traumatic Brain Injury Abstract Moderate-to-severe traumatic brain injury (TBI) is a chronic health condition with multi-systemic effects. Survivors face significant long-term functional limitations, including physical activity intolerance and disordered sleep. Persistent cardiorespiratory dysfunction is a potentially modifiable yet often overlooked major contributor to the alarmingly high long-term morbidity and mortality rates in these patients. This narrative review was developed through systematic and non-systematic searches for research relating cardiorespiratory function to moderate-to-severe TBI. The literature reveals patients who have survived moderate-to-severe TBI have ~ 25–35% reduction in maximal aerobic capacity 6–18 months post-injury, resting pulmonary capacity parameters that are reduced 25–40% for weeks to years post-injury, increased sedentary behavior, and elevated risk of cardiorespiratory-related morbidity and mortality. Synthesis of data from other patient populations reveals that cardiorespiratory dysfunction is likely a consequence of ventilator-induced diaphragmatic dysfunction (VIDD), which is not currently addressed in TBI management. Thus, cardiopulmonary exercise testing should be routinely performed in this patient population and those with cardiorespiratory deficits should be further evaluated for diaphragmatic dysfunction. Lack of targeted treatment for underlying cardiorespiratory dysfunction, including VIDD, likely contributes to physical activity intolerance and poor functional outcomes in these patients. Interventional studies have demonstrated that short-term exercise training programs are effective in patients with moderate-to-severe TBI, though improvement is variable. Inspiratory muscle training is beneficial in other patient populations with diaphragmatic dysfunction, and may be valuable for patients with TBI who have been mechanically ventilated. Thus, clinicians with expertise in cardiorespiratory fitness assessment and exercise training interventions should be included in patient management for individuals with moderate-to-severe TBI.

Can Resistance Training Improve Upper Limb Postural Tremor, Force Steadiness and Dexterity in Older Adults? A Systematic Review Abstract Background The ageing process and several health conditions may increase tremor and reduce force steadiness and dexterity, which can severely impact on function and quality of life. Resistance training can evoke a range of neuromuscular adaptions that may significantly reduce tremor and/or increase force steadiness and/or dexterity in older adults, irrespective of their health condition. Objectives The objective of this study was to systematically review the literature to determine if a minimum of 4 weeks’ resistance training can reduce postural tremor and improve force steadiness and/or dexterity in older adults, defined as aged 65 years and over. Methods An electronic search using Ovid, CINAHL, SPORTDiscus and EMBASE was performed. Risk of bias was assessed using the Cochrane Risk of Bias Tool. Results Fourteen studies met the eligibility criteria, including six randomised controlled trials and two quasi-randomised controlled trials. All eight studies that recruited healthy older adults reported significant reductions in postural tremor and/or improvements in force steadiness and dexterity. Five out of seven studies that examined older adults with a particular health condition reported some improvements in force steadiness and/or dexterity. Specifically, significant benefits were observed for older adults with chronic obstructive pulmonary disease and essential tremor; however, small or no changes were observed for individuals with osteoarthritis or stroke. Conclusions Resistance training is a non-pharmacological treatment that can reduce tremor and improve force steadiness and dexterity in a variety of older adult populations. Future research should employ randomised controlled trials with larger sample sizes, better describe training programme methods, and align exercise prescription to current recommendations for older adults.

Effects of Workplace-Based Physical Activity Interventions on Cardiorespiratory Fitness: A Systematic Review and Meta-Analysis of Controlled Trials Abstract Background Cardiorespiratory fitness is a strong predictor of all-cause mortality. Physical activity of at least moderate intensity can improve cardiorespiratory fitness. Workplaces may provide a relatively controlled setting in which to improve cardiorespiratory fitness through physical activity. Limited work has been conducted to quantify the impact of delivering physical activity in the workplace on cardiorespiratory fitness. Objective The objective of this systematic review was to quantify the effects of workplace physical activity interventions on peak oxygen consumption (VO2peak) and explore study and participant characteristics as putative moderators. Methods Seven databases were searched up to September 2018. Search terms included “workplace”, “physical activity” and “intervention”. Inclusion criteria were controlled trials where physical activity of at least moderate intensity was delivered in the workplace and compared to controls or non-active comparators; and cardiorespiratory fitness measured by actual or predicted VO2peak. Risk of bias was assessed using the PEDro scale. A random-effects meta-analysis was conducted with between-study variation quantified and then explored for putative predictors with a meta-regression. Pooled estimate uncertainty was expressed as 90% confidence intervals (CIs) and assessed against our threshold value for clinical relevance of 1 mL·kg−1·min−1. Results The final dataset consisted of 25 estimates of VO2peak from 12 trials. The pooled mean differences between intervention and control arms was a beneficial improvement of 2.7 mL·kg−1·min−1 (90% CI 1.6–3.8). The 95% prediction interval ranged from a reduction in VO2peak of − 1.1 to an improvement of 6.5 mL·kg−1·min−1. Between-study heterogeneity (τau) was ± 1.6 mL·kg−1·min−1. The meta-regression showed longer interventions (3.2 mL·kg−1·min−1; 90% CI 1.6–3.8) to have an additive effect and studies with a low risk of bias (− 2.5 mL·kg−1·min−1; 90% CI − 4.0 to − 1.0), and participants of greater baseline VO2peak (− 1.6 mL·kg−1·min−1; 90% CI − 3.6 to 0.4), and age (− 1.4 mL·kg−1·min−1; 90% CI − 3.2 to 0.3) having a lesser effect. Participant sex (percentage female) had an additive effect on VO2peak (0.4 mL·kg−1·min−1; 90% CI − 1.6 to 2.4). Conclusions Workplace-based physical activity interventions consisting of at least moderate-intensity activity improve cardiorespiratory fitness. At the present time, we surmise that no single group of employees (e.g. older employees or less fit individuals) can be definitively identified as standing to benefit more from workplace physical activity interventions than others. This demonstrates the potential utility of workplace physical activity interventions for improving cardiorespiratory fitness in a broad range of healthy employees. Protocol registration: PROSPERO (registration number: 42017057498).

Do Self-Myofascial Release Devices Release Myofascia? Rolling Mechanisms: A Narrative Review Abstract The term “self-myofascial release” is ubiquitous in the rehabilitation and training literature and purports that the use of foam rollers and other similar devices release myofascial constrictions accumulated from scar tissue, ischaemia-induced muscle spasms and other pathologies. Myofascial tone can be modulated with rollers by changes in thixotropic properties, blood flow, and fascial hydration affecting tissue stiffness. While rollers are commonly used as a treatment for myofascial trigger points, the identification of trigger points is reported to not be highly reliable. Rolling mechanisms underlying their effect on pain suppression are not well elucidated. Other rolling-induced mechanisms to increase range of motion or reduce pain include the activation of cutaneous and fascial mechanoreceptors and interstitial type III and IV afferents that modulate sympathetic/parasympathetic activation as well as the activation of global pain modulatory systems and reflex-induced reductions in muscle and myofascial tone. This review submits that there is insufficient evidence to support that the primary mechanisms underlying rolling and other similar devices are the release of myofascial restrictions and thus the term “self-myofascial release” devices is misleading.

The Effects of Cognitive Loading on Motor Behavior in Injured Individuals: A Systematic Review Abstract Background Research suggests that individuals with musculoskeletal injury may have difficulty negotiating physical tasks when they are combined with cognitive loads. Objective Our objective was to conduct a systematic review to understand the effects of increased cognitive demand on movement patterns among individuals with musculoskeletal injuries. Methods A comprehensive search of PubMed, MEDLINE, the Cumulative Index for Nursing and Allied Health Literature (CINAHL), and SPORTDiscus was conducted to find research reports that included a population that had previously experienced an ankle, knee, or low back injury, included an uninjured control group, and assessed a dual-task paradigm. Results Forty-five full-text research reports were assessed, of which 28 studies (six ankle injury, nine knee injury, and 13 low back pain studies) were included in the review. Included studies were assessed for methodological quality and the study design extracted for analysis including the participants, cognitive and physical tasks performed, as well as outcome measures (e.g., three-dimensional kinematics, center of pressure, etc.). All studies included were cross-sectional or case–control with methodological quality scores of 17.8 ± 2.2 out of a possible 22. Twenty-five of the 28 studies found changes in motor performance with dual-task conditions compared with single tasks. Furthermore, 54% of studies reported a significant group by task interaction effect, reporting at least one alteration in injured groups’ motor performance under dual-task conditions when compared with an uninjured group. Conclusion The results of this systematic review indicate that motor performance is further impaired by placing a cognitive load on individuals in populations with musculoskeletal injury. More demanding tasks such as gait appear to be more affected in injured individuals than simple balance tasks. Future investigators may want to consider the difficulty of the tasks included as well as the impact of dual-task paradigms on rehabilitation programs.