The polymorphism T1470A of the SLC16A1 gene is associated with the lactate and ventilatory thresholds but not with fat oxidation capacity in young men.

PURPOSE: To examine the association of the single nucleotide polymorphism A1470T in the SLC16A1 gene with blood lactate accumulation during a graded exercise test and its associated metaboreflex. METHODS: Forty-six Latin-American men (Age: 27 ± 6 years; Body fat: 17.5 ± 4.7%) performed a graded exercise test on a treadmill for the assessment of maximal oxygen uptake (VO2max), lactate threshold (LT), ventilatory threshold (VT) and the exercise intensity corresponding to maximal fat oxidation rate (FATmax), via capillary blood samples and indirect calorimetry. Genomic DNA was extracted from a peripheral blood sample. Genotyping assay was carried out by real-time polymerase chain reaction to identify the A1470T polymorphism (rs1049434). RESULTS: Genotypes distribution were in Hardy-Weinberg equilibrium (X2 = 5.6, p > 0.05), observing allele frequencies of 0.47 and 0.53 for the A and T alleles, respectively. No difference in VO2max, body composition nor FATmax were observed across genotypes, whereas carriers of the TT genotype showed a higher LT (24.5 ± 2.2 vs. 15.6 ± 1.7 mL kg-1 min-1, p < 0.01) and VT in comparison to carriers of the AA + AT genotypes (32.5 ± 3.3 vs. 21.7 ± 1.5 mL kg-1 min-1, p < 0.01). Both, VO2max and the A1470T polymorphism were positively associated to the LT (R2 = 0.50, p < 0.01) and VT (R2 = 0.55, p < 0.01). Only VO2max was associated to FATmax (R2 = 0.39, p < 0.01). CONCLUSION: Independently of cardiorespiratory fitness, the A1470T polymorphism is associated to blood lactate accumulation and its associated ventilatory response during submaximal intensity exercise. However, the A1470 polymorphism does not influence fat oxidation capacity during exercise in young men.

European fitness landscape for children and adolescents: updated reference values, fitness maps and country rankings based on nearly 8 million test results from 34 countries gathered by the FitBack network.

OBJECTIVES: (1) To develop reference values for health-related fitness in European children and adolescents aged 6-18 years that are the foundation for the web-based, open-access and multilanguage fitness platform (FitBack); (2) to provide comparisons across European countries. METHODS: This study builds on a previous large fitness reference study in European youth by (1) widening the age demographic, (2) identifying the most recent and representative country-level data and (3) including national data from existing fitness surveillance and monitoring systems. We used the Assessing Levels of PHysical Activity and fitness at population level (ALPHA) test battery as it comprises tests with the highest test-retest reliability, criterion/construct validity and health-related predictive validity: the 20 m shuttle run (cardiorespiratory fitness); handgrip strength and standing long jump (muscular strength); and body height, body mass, body mass index and waist circumference (anthropometry). Percentile values were obtained using the generalised additive models for location, scale and shape method. RESULTS: A total of 7 966 693 test results from 34 countries (106 datasets) were used to develop sex-specific and age-specific percentile values. In addition, country-level rankings based on mean percentiles are provided for each fitness test, as well as an overall fitness ranking. Finally, an interactive fitness platform, including individual and group reporting and European fitness maps, is provided and freely available online (www.fitbackeurope.eu). CONCLUSION: This study discusses the major implications of fitness assessment in youth from health, educational and sport perspectives, and how the FitBack reference values and interactive web-based platform contribute to it. Fitness testing can be conducted in school and/or sport settings, and the interpreted results be integrated in the healthcare systems across Europe.

The evaluation of oral and dental health and behavioural risk among ultra-endurance athletes: a cross-sectional epidemiological study.

This study assessed for the first time the oral and dental health of ultra-trail athletes. We also confirmed and quantified the scale of their exposure to oral health risk factors. This was a cross-sectional study using data from a survey among runners who enlisted in the 2020 edition of the UT4M races (Ultra-Trail des 4 Massifs). The dental health of 84% of the participants was "good" or "very good". The nutritional intake during effort comprised foods liable to induce tooth decay (energy bars (55%), sugar-rich gels and fruit confectionary (40%)) and snacking was frequent (39%). More than 3/5 of runners saw a dentist for preventive check-ups. The more runners participate in races the more likely they are to have oral hygiene strategies during competitions (aOR = 1.85, p ≤ 0.05). The oral health of ultra-trail runners is better than that of the average French adult population. Regular dental hygiene and preventive dental consultations appear to counterbalance the risks that we evidenced.

The role of physical arm function and demographic disparities in breast cancer survivors' ability to return to work.

PURPOSE: Ability to return to work (RTW) is an important aspect of breast cancer that is limited for many survivors. With 90% survivorship in the USA, it is imperative that focus shifts toward the improvement of physical arm function to improve survivors' ability to RTW. This narrative review discusses the role of physical arm function and demographic disparities in breast cancer survivor RTW. METHODS: Literature on physical function, arm function, and demographic disparities following breast cancer treatment and their implications for RTW is discussed. RESULTS: The ability to RTW is a key component of recovery for breast cancer survivors, but challenges and inequalities persist. Treatment effects can induce and prolong functional disability, affecting survivors' ability to RTW. These effects may be compounded for survivors whose occupation requires physical arm function. The RTW landscape, including the occupations survivors have, the physical function required for job tasks, and availability of workplace accommodations, is also unclear. Additional demographic disparities (e.g., income, live in rural area) exist, but the extent to which these factors influence RTW is not well understood. More work is needed to understand the compounded impact of treatment effects, demographic disparities, and occupational factors on RTW. Multidisciplinary rehabilitation that includes occupational counseling and exercise is a promising approach, but widespread adoption in the US healthcare model presents an ongoing challenge. Areas for further research are highlighted. CONCLUSION: There is an incomplete understanding of the effects of treatment on physical arm function and the role of demographic disparities on breast cancer survivor RTW.

The Relevance of Dual Tasking for Improving Trunk Muscle Endurance After Back Surgery.

OBJECTIVE: To determine the effect of dual tasking on trunk muscle endurance in patients after lumbar diskectomy. DESIGN: Cross-sectional study. SETTING: Rehabilitation hospital setting. PARTICIPANTS: Individuals (N=14) undergoing primary lumbar diskectomy. INTERVENTION: Using a randomized design on 2 separate days, muscle endurance was evaluated during prone bridging and Biering-Sorensen tests. Each test was randomly performed under 2 cognitive conditions: single task without cognitive condition and self-regulated dual task (ie, mathematical task). MAIN OUTCOME MEASURES: The primary outcomes were time to failure and pain assessed by the visual analog scale from 0 to 100 mm. The secondary outcomes were kinesiophobia assessed by the Tampa Scale and disability assessed by the Oswestry Disability Index. Associations were tested using a repeated measures analysis of variance with relevant interaction test. RESULTS: A significant interaction between condition, endurance tests, and kinesiophobia (P=.005) was found. The post hoc comparison showed positive effects between cognitive conditions in both endurance tests (prone bridging test: mean difference, 15.7s; 95% confidence interval [CI], 7.5-24s; P=.001; Biering-Sorensen test: mean difference, 7.9s; 95% CI, 1.9-14s; P=.014). The linear regression analysis between the Tampa Scale for Kinesiophobia and the difference of time to failure between cognitive conditions showed a positive correlation only during the Biering-Sorensen test (r=0.80; P=.001). CONCLUSIONS: A self-regulated dual task increases trunk muscle endurance in patients after lumbar diskectomy. The results suggest that the difference observed in time to failure between the single task and dual task is associated with fear avoidance, especially during back extension. This strategy seems especially relevant for patients with high levels of fear avoidance and may be used to improve trunk muscle endurance.

Assessing Physical Function and Mobility following Pediatric Traumatic Brain Injury with the NIH Toolbox Motor Battery: A Feasibility Study.

AIMS: Traumatic brain injury (TBI) can impair physical function in children. The NIH Toolbox Motor Battery (NIHTB-M) was designed to be a brief assessment of physical function, but no studies have examined its use in children with TBI. This study aims to describe the feasibility of using the NIHTB-M to assess children with TBI. METHODS: The NIHTB-M was administered to children with TBI 2 weeks (n = 22) and/or 6 months (n = 23) following injury. This descriptive study summarizes participant performance, administration challenges, and the association between NIHTB-M scores, participant characteristics, and subjective report of physical function. RESULTS: Of the NIHTB-M domains, deficits in endurance and balance were most prevalent. Children aged 5 to 16 years could complete the assessment per administration guidelines, except for a few cases (n = 3) where orthopedic injuries limited participation. Younger children (aged 3 to 4) had difficulty following the NIHTB-M directions. Technological issues impacted balance assessment in several cases (n = 6). CONCLUSION: The NIHTB-M is brief to administer, generally well tolerated by school-aged children and, despite occasional technological challenges, is a feasible performance-based battery for assessment of children with TBI for clinical and research purposes. Additional investigation of psychometric properties and ceiling and floor effects is needed.

[Assessment of heart's changes of elite Chinese male weightlifter by speckle tracking echocardiography].

OBJECTIVE: To evaluate the changes of heart structure and function in elite Chinese weightlifters by spot tracking technique. METHODS: Chinese elite male weightlifters (weightlifter group, n=16) and age-matched healthy men (control group, n=16) were included as subjects. Transthoracic echocardiography and speckle-tracking automatic functional imaging were used for two-dimensional myocardial strain measurements. RESULTS: The thickness of septum and left ventricular (LV) posterior wall and the myocardial mass index of LV were all higher than those of the control group [(9.3±1.3) mm vs. (8.0±0.4) mm, (9.2±0.8) mm vs. (8.0±0.8) mm, (77.8±12.8) g/m2 vs. (67.8±11.2) g/m2, all P < 0.05]. Although the LV ejection fraction (LVEF) and global long axis strain value (LVGLS) were not significantly different from those in the control group, the LV mean Sm and Em reflecting the systolic and diastolic functions of the LV were lower than those in the control group (P < 0.05). Further myocardial strain analysis showed that the absolute value of the long axial strain of the basal anteroseptal and mid-inferoseptal segments of the weightlifters were significantly lower than those of the control group [|(-15.1±4.2)%|vs.|(-18.7±3.0)%|, |(-18.8±2.6)%|vs.|(-21.3±2.8)%|, all P < 0.05]. There was no significant difference in other segments. The athletes were divided into two groups according to their best performance in the National Youth Games. The athletes were divided into two sub-groups according to their performance in the National Youth Games. The thickness of the septum in the sub-group with better performance (who ranked the 1st to 8th) was larger [(10.2±1.1) mm vs. (8.5±1.0) mm, P < 0.05], and the absolute value of the long-axis strain in the mid-inferoseptal segment was lower [|(-17.1±2.1)%|vs.|(-20.4±2.1)%|, P < 0.05]. CONCLUSION: The thickening of septum is more obvious in the excellent weightlifters, accompanied by the decrease of myocardial systolic function. The speckle-tracking technique of echocardiography can identify the changes of the heart structure and function of elite athletes at an early stage, which may provide a basis for sports medicine supervision and the selection of excellent talents.

Training for a (half-)marathon: Training volume and longest endurance run related to performance and running injuries.

OBJECTIVE: Examine the associations of training volume and longest endurance run with (half-)marathon performance and running-related injuries (RRIs) in recreational runners. MATERIALS AND METHODS: During the preparation for and directly after the running event, 556 participants of a half marathon and 441 participants of a marathon completed three questionnaires on RRIs, average weekly training volume and the longest endurance run. With finish time, decline in pace during the running event and RRIs as dependent variables, linear and logistic regression analyses were performed to test the associations with weekly training volume and the longest endurance run. RESULTS: In half-marathon runners, a high training volume (>32 km/wk) (ß -4.19, 95% CI: -6.52;-1.85) and a long endurance run (>21 km) (ß -3.87, 95% CI: -6.31;--1.44) were associated with a faster finish time, while a high training volume (ß -1.81, 95% CI: -3.49;-0.12) and a long endurance run (ß -1.89, 95% CI: -3.65;-0.12) were also related to less decline in pace. In marathon runners, a low training volume (<40 km/wk) was related to a slower finish time (ß 6.33, 95% CI: 0.18;12.48) and a high training volume (>65 km/wk) to a faster finish time (ß -14.09, 95% CI: -22.47;-5.72), while a longest endurance run of <25 km was associated with a slower finish time (ß 13.44, 95% CI: 5.34;21.55). No associations between training characteristics and RRIs were identified. CONCLUSIONS: Preparation for a (half-)marathon with a relatively high training volume and long endurance runs associates with a faster finish time, but does not seem related to an increased injury risk.

Reduced maximal aerobic capacity after COVID-19 in young adult recruits, Switzerland, May 2020.

In March 2020, we observed an outbreak of COVID-19 among a relatively homogenous group of 199 young (median age 21 years; 87% men) Swiss recruits. By comparing physical endurance before and in median 45 days after the outbreak, we found a significant decrease in predicted maximal aerobic capacity in COVID-19 convalescent but not in asymptomatically infected and SARS-CoV-2 naive recruits. This finding might be indicative of lung injury after apparently mild COVID-19 in young adults.

Muscle endurance deficits in myositis patients despite normal manual muscle testing scores.

INTRODUCTION: It is unclear whether quantitating muscle endurance adds nonredundant information useful for the care of patients with muscular disease. METHODS: Records were retrospectively reviewed for all Johns Hopkins Myositis Center patients with a muscle endurance assessment (n = 128, 226 patient-visits). Muscle endurance and strength were quantitated with the Myositis Functional Index-2 (FI2) and manual muscle testing (MMT), respectively. RESULTS: Composite FI2 muscle endurance scores were comparable in inclusion body myositis (n = 58), dermatomyositis (n = 31), and polymyositis (n = 39). Overall, muscle endurance correlated with and evolved similarly to strength, inversely to serum creatine kinase. However, in patients with normal or near-normal strength (mean MMT > 9.75/10), muscle endurance was typically abnormal and highly variable (mean FI2, 5.6/10; interquartile range, 3.3-7.8/10). DISCUSSION: Muscle endurance testing may identify muscle impairment inadequately described by MMT, particularly in patients with high MMT scores. Muscle Nerve 59:70-75, 2019.

Endurance and resistance training in patients with acute leukemia undergoing induction chemotherapy-a randomized pilot study.

PURPOSE: Acute leukemia (AL) and its initial treatment can impair physical functioning and capacity significantly. Exercise as a countermeasure has been investigated in few studies confirming its feasibility and safety during intensive induction chemotherapy, but the relative effects of diverse exercise programs have not been analyzed. Therefore, we aimed to investigate independent effects of endurance and resistance training on physical capacity and quality of life (QOL). METHODS: Twenty-nine adult AL patients were randomly allocated to an endurance (EG), resistance (RG), or control (CG) group. The intervention took place during induction chemotherapy with three exercise sessions per week for 30-45 min each. Endurance capacity at individual anaerobic threshold, maximum knee extension and flexion strength, standardized phase angle (SPA), and QOL were measured at baseline prior to induction chemotherapy and before discharge. RESULTS: Endurance capacity changed in neither the EG, RG, or CG (P = 0.104); descriptively, the EG (- 0.05 W/kg) and RG (- 0.04 W/kg) exhibited a smaller decrease than CG (- 0.22 W/kg). We noted a significant difference in knee extension strength (P = 0.002); RG improved their maximum strength (+ 0.14 Nm/kg), while the EG's (- 0.13 Nm/kg) and CG's (- 0.19 Nm/kg) was significantly reduced. QOL and SPA revealed no change after the intervention. CONCLUSIONS: We conclude that resistance training is a key component when exercising during induction chemotherapy: it improved maximum strength, but also influenced endurance capacity even during intensive treatment. Considering the prognostic value of physical function, we strongly propose integrating exercise, especially resistance-based training, already during induction chemotherapy to preserve AL patients' physical capacity and functional status.

Effects of chronic beetroot juice supplementation on maximum oxygen uptake, velocity associated with maximum oxygen uptake, and peak velocity in recreational runners: a double-blinded, randomized and crossover study.

PURPOSE: This study investigated the effects of chronic 3-day beetroot juice (BRJ) supplementation on maximum oxygen uptake (VO2max), velocity associated with VO2max(vVO2max), and peak velocity (Vpeak) in recreational runners. METHODS: Thirteen male recreational runners (age 28.2 ± 3.0 years, height 176.8 ± 0.1 cm, body mass 74.4 ± 9.5 kg) performed four tests on a treadmill in a randomized, double-blind, crossover design: two maximum incremental tests to determine VO2max and vVO2max, and two tests to determine Vpeak. Trials were performed following 3 days of supplementation of NO3--rich BRJ in natura (8.4 mmol NO3- day- 1) or BRJ NO3--depleted placebo (0.01 mmol NO3- day- 1), with the last dose being ingested 2 h before each test. During the tests, maximum heart rate (HRmax), maximal rating of perceived exertion (RPEmax), pre- and post-test glucose concentrations (Glucpre, Glucpost), and peak blood lactate concentration were determined. RESULTS: VO2max was higher following BRJ vs PLA (46.6 ± 6.4 vs 45.1 ± 5.8 mL kg- 1 min- 1; P = 0.022), as well as vVO2max (14.5 ± 0.8 vs 13.9 ± 1.0 km h- 1P = 0.024) and Vpeak (15.5 ± 1.1 vs 15.2 ± 1.2 km h- 1P = 0.038), with no differences in the other variables. CONCLUSION: Consumption of NO3--rich BRJ in natura (8.4 mmol NO3- day- 1) once per day for 3 days improved VO2max, vVO2max and Vpeak in recreational runners without changing the other analyzed variables.

Effects of branched-chain amino acid supplementation and/or aerobic exercise on mouse sperm quality and testosterone production.

Individuals who regularly exercise utilise dietary supplements to enhance their exercise routine and to increase lean mass. Branched-chain amino acids (BCAAs) are a popular supplement and have been shown to produce a number of beneficial effects in rodent and human models. Therefore, in the present study, the effect of exercise and/or BCAA on sperm parameters and testes tissue was assessed. C57BL6 male mice were divided to six groups; Control, Exercise (Exc), BCAA (consumes 20 mg BCAAs), BCAA+ (consumes 60 mg BCAAs), BCAA/Exc (consumes 20 mg BCAAs during aerobic training) and BCAA+/Exc (consumes 60 mg BCAAs during aerobic training). After 8 weeks of exercise and oral treatment with BCAA; testes and epididymides were dissected, and sperm function and plasma testosterone were assessed. Exercise significantly improved sperm motility and plasma testosterone in Exercise groups with or without BCAA. Percentage of sperm lipid peroxidation was significantly decreased in Exercise group, while intensity of lipid peroxidation at the same group has significantly increased. Epithelium diameters, meiotic index and Johnson' grade did not show any changes between groups. Unlike intensive exercise, endurance exercise along with modest supplementation of BCAAs, but not an overdose, may have some synergic effect on sperm function and testosterone production.

Back Muscle Function in Older Women With Age-Related Hyperkyphosis: A Comparative Study.

OBJECTIVE: The purpose of this study was to compare static maximal back extensor muscle force, endurance, and characteristics of flexion relaxation phenomenon (FRP) in older women with and without age-related hyperkyphosis. METHODS: Maximum back extensor force and endurance measured in a sitting position with a designed load cell setup; appearance, onset, and offset angles of FRP; and extension relaxation ratio (ERR) during a dynamic flexion-extension task were compared between 24 older women with hyperkyphosis (thoracic kyphosis angle ≥50°), mean age 65 ± 4.4 years, and 24 older women without hyperkyphosis (thoracic kyphosis angle ≪50°), mean age 63 ± 4.3 years. Variables of force, endurance, angles of FRP, and ERR were analyzed using an independent sample t test. A χ2 test was used to identify differences between groups in FRP appearance. RESULTS: Static back extensor force and endurance were significantly lower among those with versus those without hyperkyphosis (P ≪ .001). Although the 2 groups did not differ in FRP appearance and ERR in the superficial erector spinal muscles (P ≫ .05), FRP in the hyperkyphosis group started sooner and ended later than in the group without hyperkyphosis (P ≪ .05). CONCLUSION: Our study indicates that women with age-related hyperkyphosis had decreased static maximal force and endurance of the back extensor muscles and prolonged myoelectrical silence of the superficial erector spinal muscles. Reduced endurance of the superficial erector spinal muscles may trigger early onset of FRP and prolonged relaxation of these muscles.

Effects of Melatonin on the Body Composition, Physical Performance, and Blood Erythrocyte Indexes of C57Bl/6J Mice Exposed to Continuous Illumination.

Male C57Bl/6J mice were exposed to daily 24-h illumination over 14 days and daily intragastrically received melatonin (1 mg/kg) or water (placebo). Controls were kept under standard day/night (14/10 h) conditions. Melatonin prevented the development of anemia in mice exposed to continuous illumination, which was proven by higher blood hemoglobin levels by the end of the experiment in melatonin-treated animals in comparison with the placebo group. Studies by the low-field NMR spectrometry detected lower lean body mass, total body water, and especially, fat content (by ~13%) in animals receiving placebo. Melatonin treatment led to an increase in the lean body mass and total body water on day 7 (in comparison with the placebo group) without affecting fat mass. On day 14 of continuous illumination, lean body mass increased in comparison with the corresponding parameter in the control and placebo groups. Melatonin had no effect on the physical endurance of mice exposed to continuous illumination (assessed by the grid hanging test).

[Influence of coagulated egg melange on the physical endurance of growing male Wistar rats: physiological and biochemical assessment].

Melange, is one of the most commonly used products of egg processing, however, its use for the production of functional foods is limited by its liquid consistency. The range of functional foods, including those that increase physical endurance and working ability, can be expanded by using the coagulated form of the melange. Thus, the preclinical testing of the nutritional value of coagulated melange and the effect of its consumption on the physical endurance of laboratory animals is relevant. The aim of this research was the experimental comparative physiological and biochemical in vivo evaluation of the effects of coagulated melange consumption by Wistar male rats on their growth indices and physical endurance. Material and methods. Samples of the lyophilized egg melange (EM) and coagulated egg melange (CEM) were used as objects of the research The experiment was conducted with the use of 45 growing male Wistar rats with initial body weight 80±5 g. According to the preliminary training results, 27 animals were selected for further experiment. The motor function was evaluated by means of grip test. The rats were randomized into 2 experimental groups according to their weight and grip strength. Animals were treated for 32 days with isocaloric and isonitrogenic semi-synthetic diets with EM and CEM as protein component (25% of the dry weight), consequently. The grip test was conducted once per week, two days a week animals were trained on the treadmill for 10 min. On the 31st day of the experiment, animals were exposed to exhaustive training till total exhaustion. On the 32nd day of experiment animals were decapitated under light ether anesthesia. The concentration of glucose, triglycerides, cholesterol (CHL), high-density lipoproteins (HDL) and low-density lipoproteins (LDL) was determined in the blood serum. Results and discussion. The greater consumption of food (20±1 g/rat/day) containing CEM by animals corresponded to a greater increase (204±9%) of their body weight over the entire experiment period compared with animals that received EM (13±1 g/rat/day; 160±9%, respectively, p≤0.05). An increase in the intake of food containing CEM had a pronounced positive effect on the physical endurance of the animals, assessed in the grip test. For the 21 days of the experiment, this indicator increased by 26% in rats consuming EM, whereas in rats consuming CEM, the grip strength increased more significantly - by 42%. Consumption of CEM by animals increased the run time (33.8±1.4 min) and the distance covered (557±35 m) in the treadmill test before the exhaustion in comparison with similar indicators for animals that received EM (24.8±2.5 min and 365±50 m, respectively , p≤0.05). The obtained results indicate an increased resistance of animals treated with CEM to exhausting physical loads. Conclusion. The consumption of CEM by growing Wistar male rats increased more effectively their growth and physical endurance in comparison with animals treated with non-coagulated egg melange. These results show the prospective of the use of CEM as a functional food ingredient in specialized foods, enhancing physical endurance and working ability.

Body size and physical exercise, and the risk of multiple sclerosis.

BACKGROUND: Whether large body size increases multiple sclerosis (MS) risk in men is not well understood. Concurrently, physical exercise could be an independent protective factor. OBJECTIVE: To prospectively investigate the association between body mass index (BMI) and aerobic fitness, indicators of body size and exercise, and MS risk in men. METHODS: We performed a population-based nested case-control study within the historical cohort of all Norwegian men, born in 1950-1975, undergoing mandatory conscription at the age of 19 years. 1016 cases were identified through linkage to the Norwegian MS registry, while 19,230 controls were randomly selected from the cohort. We estimated the effect of BMI and fitness at conscription on MS risk using Cox regression. RESULTS: Higher BMI (≥25 vs 18.5-<25 kg/m2) was significantly associated with increased MS risk (adjusted relative risk (RRadj) = 1.36, 95% confidence interval (CI): 1.05-1.76). We also found a significant inverse association between aerobic fitness (high vs low) and MS risk independent of BMI (RRadj = 0.69, 95% CI: 0.55-0.88, p-trend = 0.003), remaining similar when men with MS onset within 10 years from conscription were excluded ( p-trend = 0.03). CONCLUSION: These findings add weight to evidence linking being overweight to an increased MS risk in men. Furthermore, they suggest that exercise may be an additional modifiable protective factor for MS.

Heritability estimates of endurance-related phenotypes: A systematic review and meta-analysis.

The aim of this study was to clarify heritability estimates for endurance-related phenotypes and the underlying factors affecting these estimates. A systematic literature search was conducted for studies reporting heritability estimates of endurance-related phenotypes using the PubMed database (up to 30 September 2016). Studies that estimated the heritability of maximal oxygen uptake (V˙O2max), submaximal endurance phenotypes, and endurance performance were selected. The weighted mean heritability for endurance-related phenotypes was calculated using a random-effects model. A total of 15 studies were selected via a systematic review. Meta-analysis revealed that the weighted means of the heritability of V˙O2max absolute values and those adjusted for body weight and for fat-free mass were 0.68 (95% CI: 0.59-0.77), 0.56 (95% CI: 0.47-0.65), and 0.44 (95% CI: 0.13-0.75), respectively. There was a significant difference in the weighted means of the heritability of V˙O2max across these different adjustment methods (P < .05). Moreover, there was evidence of statistical heterogeneity in the heritability estimates among studies. Meta-regression analysis revealed that sex could partially explain the heterogeneity in the V˙O2max heritability estimates adjusted by body weight. For submaximal endurance phenotypes and endurance performance, the weighted mean heritabilities were 0.49 (95% CI: 0.33-0.65) and 0.53 (95% CI: 0.27-0.78), respectively. There was statistically significant heterogeneity in the heritability estimates reported among the studies, and we could not identify the specific factors explaining the heterogeneity. Although existing studies indicate that genetic factors account for 44%-68% of the variability in endurance-related phenotypes, further studies are necessary to clarify these values.

Effect of Elastic Therapeutic Taping on Abdominal Muscle Endurance in Patients With Chronic Nonspecific Low Back Pain: A Randomized, Controlled, Single-Blind, Crossover Trial.

OBJECTIVE: The purpose of this study was to determine the immediate effect of elastic therapeutic taping and sham taping of the abdominal musculature on maximum hold time of endurance tests in patients with chronic nonspecific low back pain (CNLBP). METHODS: Twenty-six people with CNLBP and 26 asymptomatic individuals were included in this study. The CNLBP participants were allocated to an elastic therapeutic tape group or a sham tape group. Standard adhesive elastic therapeutic tape was utilized for facilitatory application in the elastic therapeutic tape group. The elastic therapeutic tape group received real elastic therapeutic taping on the transversus abdominis and internal obliques, and the sham tape group received sham elastic therapeutic taping application. For the sham group, the elastic therapeutic tape was positioned horizontally above the navel and applied without tension. After a wash-out period, each CNLBP participant was switched to the other group. Outcome measures included maximum hold time of supine isometric chest raise, supine double straight-leg raise, and abdominal drawing in maneuver. RESULTS: The CNLBP participants had lower maximum hold time compared to the asymptomatic individuals (P ≤ .01). Following taping, both groups showed an increase in the maximum hold time (mean difference = 4.43 - 50.69 seconds; P ≤ .02). Although there was no difference between the results of both groups (P ≥ .12), effect sizes were large for the elastic therapeutic tape group (Cohen's d = -1.93 to -1.00). CONCLUSIONS: The results suggest that the maximum hold time of endurance tests was decreased in CNLBP patients compared to healthy participants. The application of both elastic therapeutic tape and sham tape to the transversus abdominis and internal obliques produced short-term improvement in abdominal endurance. There was no statistically significant difference between the results of elastic therapeutic tape and sham tape.

Changes in physiological and performance variables in non-professional triathletes after taking part in an Olympic distance triathlon.

Given increasing popularity of triathlon, the objective of this study was to evaluate the acute effects upon the health of triathletes. To do so, with a sample of 23 male athletes (34.4 ± 7.9 years old), an assessment was carried out both before and after an Olympic distance triathlon, of the bodily composition, the jumping ability and the BORG and VAS scales, as well as a blood analysis of the following: Lactate (mmol/L), Hematrocrit (%), Glucose (mg/dL), Total proteins (mg/dL), Triglycerides (mg/dL), Bilirubin (mg/dL), GOT (IU/L), GPT (IU/L), LDH (IU/L), CPK (IU/L). The results showed an increase (p < 0.001) in the different markers of metabolic stress and muscular damage following the triathlon, but always within a normal range considered to be healthy, with the exception of CPK (IU/L) (PRE 149.33 ± 108.16 vs POST 290.10 ± 102.48). Therefore, it would seem that competing in an Olympic-distance triathlon does not pose health risks for trained subjects.