Impact of probiotic supplementation on exercise endurance among non-elite athletes: study protocol for a randomized, placebo-controlled, double-blind, clinical trial.

BACKGROUND: Some probiotics appear to improve athletic performance, endurance, and recovery after intense exercise. Other formulations may provide performance-related benefits via immune and gastrointestinal functions in athletic individuals. However, few formulations have been studied for both types of effects among non-elite athletes. The primary objective of this study is to assess the ergogenic effects of a probiotic on high-intensity endurance running performance in non-elite runners. Secondary objectives include assessment of perceived exertion, blood chemistry, immune and stress biomarkers, cold and flu symptoms, and gastrointestinal health after the probiotic intervention. METHODS: This 9-week randomized, placebo-controlled, double-blind, parallel trial will assess the ergogenic effects of a probiotic (5 billion colony-forming units/day, for 6 weeks) in healthy, non-elite runners (N=32; 18-45 years). Participants will be monitored via daily and weekly questionnaires during the 2-week pre-baseline, 6-week intervention, and 1-week washout. Questionnaires will inquire about activity, muscle soreness, gastrointestinal symptoms, cold and flu symptoms, stool form and frequency, and adverse events. During the pre-baseline visit, maximal oxygen uptake (V̇O2 max) is assessed to set appropriate individualized workload settings for the treadmill time-to-exhaustion endurance tests. These time-to-exhaustion endurance running tests will be completed at an intensity of 85% VO2max at baseline and final visits. During these tests, self-perceived exercise effort will be rated via the Borg Rating of Perceived Exertion scale and finger sticks assessing capillary blood glucose and lactate concentrations will be collected every 3 min. Additional questionnaires will assess diet and motivation to exercise. Body composition will be assessed using air displacement plethysmography at the baseline and final visits. Hypotheses will be tested using two-sided tests, and a linear model and with a type I error rate of α=0.05. Primary and secondary outcomes will be tested by comparing results between the intervention groups, adjusting for baseline values. DISCUSSION: These results will build evidence documenting the role of probiotics on running endurance performance and physiological responses to exercise in non-elite athletes. Understanding the potential mechanisms of probiotic effects and how they mitigate the intestinal or immune discomforts caused by running could provide additional strategy means to help runners improve their performance. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov NCT04588142 . Posted on October 19, 2020. PROTOCOL VERSION: July 2, 2021, version 1.2.

The Influence of Nutrition and Physical Activity on Exercise Performance after Mild COVID-19 Infection in Endurance Athletes-CESAR Study.

COVID-19 and imposed restrictions are linked with numerous health consequences, especially among endurance athletes (EA). Unfavorable changes in physical activity and nutrition may affect later sports and competition performance. The aims of this study were: (1) to assess the impact of COVID-19 infection and pandemic restrictions on the nutrition and physical activity of EAs and (2) to compare them with the results of cardiopulmonary exercise testing (CPET). In total, 49 EAs (nmale = 43, nfemale = 6, mean age = 39.9 ± 7.8 year., height = 178.4 ± 6.8 cm, weight = 76.3 ± 10.4 kg; BMI = 24.0 ± 2.6 kg·m−2) underwent pre- and post-COVID-19 CPET and fulfilled the dietary and physical activity survey. COVID-19 infection significantly deteriorated CPET performance. There was a reduction in oxygen uptake and in heart rate post-COVID-19 (both p < 0.001). Consuming processed meat and replacing meat with plant-based protein affected blood lactate concentration (p = 0.035). Fat-free mass was linked with consuming unsaturated fatty acids (p = 0.031). Adding salt to meals influenced maximal speed/power (p = 0.024) and breathing frequency (p = 0.033). Dietary and Fitness Practitioners and Medical Professionals should be aware of possible COVID-19 infection and pandemic consequences among EA. The results of this study are a helpful guideline to properly adjust the treatment, nutrition, and training of EA.

Effects of air pollution exposure on inflammatory and endurance performance in recreationally trained cyclists adapted to traffic-related air pollution.

The aim of the present study was to analyze the effects of traffic-related air pollution (TRAP) on markers of inflammatory, neuroplasticity, and endurance performance-related parameters in recreationally trained cyclists who were adapted to TRAP during a 50-km cycling time trial (50-km cycling TT). Ten male cyclists performed a 50-km cycling TT inside an environmental chamber located in downtown Sao Paulo (Brazil), under TRAP or filtered air conditions. Blood samples were obtained before and after the 50-km cycling TT to measure markers of inflammatory [interleukin-6 (IL-6), C-reactive protein (CRP), interleukin-10 (IL-10), intercellular adhesion molecule-1 (ICAM-1)] and neuroplasticity [brain-derived neurotrophic factor (BDNF)]. Rating of perceived exertion (RPE), heart rate (HR), and power output (PO) were measured throughout the 50-km cycling TT. There were no significant differences between experimental conditions for responses of IL-6, CRP, and IL-10 (P > 0.05). When compared with exercise-induced changes in filtered air condition, TRAP provoked greater exercise-induced increase in BDNF levels (TRAP = 3.3 ± 2.4-fold change; Filtered = 1.3 ± 0.5-fold change; P = 0.04) and lower exercise-induced increase in ICAM-1 (Filtered = 1.1 ± 0.1-fold change; TRAP = 1.0 ± 0.1-fold change; P = 0.01). The endurance performance-related parameters (RPE, HR, PO, and time to complete the 50-km cycling TT) were not different between TRAP and filtered air conditions (P > 0.05). These findings suggest that the potential negative impacts of exposure to pollution on inflammatory, neuroplasticity, and performance-related parameters do not occur in recreationally trained cyclists who are adapted to TRAP.

Trends in Participation, Sex Differences and Age of Peak Performance in Time-Limited Ultramarathon Events: A Secular Analysis.

Background and Objectives: Increases in the number of participants in time-limited ultra-marathons have been reported. However, no information is available regarding the trends in participation, performance and age in 12 h and 24 h time-limited events. The aim of the study was to describe the trends in runners' participation, performance and age in 12 h and 24 h ultra-marathons for both sexes and to identify the age of peak performance, taking into account the ranking position and age categories. Materials and Methods: The sample comprised 210,455 runners in time-limited ultra-marathons (female 12 h = 23,706; female 24 h = 28,585; male 12 h = 61,594; male 24 h = 96,570) competing between 1876 and 2020 and aged 18 to 86 years. The age of peak performance was tested according to their ranking position (first-third; fourth-tenth and >tenth position) and taking into account their running speed in different age categories (<30 years; 31-40 years; 41-50 years; 51-60 years; >60 years), using the Kruskal-Wallis test, followed by the Bonferroni adjustment. Results: An increase in the number of participants and a decrease in running speed were observed across the years. For both events, the sex differences in performance decreased over time. The sex differences showed that male runners performed better than female runners, but the lowest differences in recent years were observed in the 24 h ultra-marathons. A positive trend in age across the years was found with an increase in mean age ("before 1989" = 40.33 ± 10.07 years; "1990-1999" = 44.16 ± 10.37 years; "2000-2009" = 45.99 ± 10.33 years; "2010-2020" = 45.62 ± 10.80 years). Male runners in 24 h races were the oldest (46.13 ± 10.83 years), while female runners in 12 h races were the youngest (43.46 ± 10.16 years). Athletes ranked first-third position were the youngest (female 12 h = 41.19 ± 8.87 years; female 24 h = 42.19 ± 8.50 years; male 12 h = 42.03 ± 9.40 years; male 24 h = 43.55 ± 9.03 years). When age categories were considered, the best performance was found for athletes aged between 41 and 50 years (female 12 h 6.48 ± 1.74 km/h; female 24 h 5.64 ± 1.68 km/h; male 12 h 7.19 ± 1.90 km/h; male 24 h 6.03 ± 1.78 km/h). Conclusion: A positive trend in participation in 12 h and 24 h ultra-marathons was shown across the years; however, athletes were becoming slower and older. The fastest athletes were the youngest ones, but when age intervals were considered, the age of peak performance was between 41 and 50 years.

Potential Long-Term Health Problems Associated with Ultra-Endurance Running: A Narrative Review.

It is well established that physical activity reduces all-cause mortality and can prolong life. Ultra-endurance running (UER) is an extreme sport that is becoming increasingly popular, and comprises running races above marathon distance, exceeding 6 h, and/or running fixed distances on multiple days. Serious acute adverse events are rare, but there is mounting evidence that UER may lead to long-term health problems. The purpose of this review is to present the current state of knowledge regarding the potential long-term health problems derived from UER, specifically potential maladaptation in key organ systems, including cardiovascular, respiratory, musculoskeletal, renal, immunological, gastrointestinal, neurological, and integumentary systems. Special consideration is given to youth, masters, and female athletes, all of whom may be more susceptible to certain long-term health issues. We present directions for future research into the pathophysiological mechanisms that underpin athlete susceptibility to long-term issues. Although all body systems can be affected by UER, one of the clearest effects of endurance exercise is on the cardiovascular system, including right ventricular dysfunction and potential increased risk of arrhythmias and hypertension. There is also evidence that rare cases of acute renal injury in UER could lead to progressive renal scarring and chronic kidney disease. There are limited data specific to female athletes, who may be at greater risk of certain UER-related health issues due to interactions between energy availability and sex-hormone concentrations. Indeed, failure to consider sex differences in the design of female-specific UER training programs may have a negative impact on athlete longevity. It is hoped that this review will inform risk stratification and stimulate further research about UER and the implications for long-term health.

Three weeks of a home-based "sleep low-train low" intervention improves functional threshold power in trained cyclists: A feasibility study.

BACKGROUND: "Sleep Low-Train Low" is a training-nutrition strategy intended to purposefully reduce muscle glycogen availability around specific exercise sessions, potentially amplifying the training stimulus via augmented cell signalling. The aim of this study was to assess the feasibility of a 3-week home-based "sleep low-train low" programme and its effects on cycling performance in trained athletes. METHODS: Fifty-five trained athletes (Functional Threshold Power [FTP]: 258 ± 52W) completed a home-based cycling training program consisting of evening high-intensity training (6 × 5 min at 105% FTP), followed by low-intensity training (1 hr at 75% FTP) the next morning, three times weekly for three consecutive weeks. Participant's daily carbohydrate (CHO) intake (6 g·kg-1·d-1) was matched but timed differently to manipulate CHO availability around exercise: no CHO consumption post- HIT until post-LIT sessions [Sleep Low (SL), n = 28] or CHO consumption evenly distributed throughout the day [Control (CON), n = 27]. Sessions were monitored remotely via power data uploaded to an online training platform, with performance tests conducted pre-, post-intervention. RESULTS: LIT exercise intensity reduced by 3% across week 1, 3 and 2% in week 2 (P < 0.01) with elevated RPE in SL vs. CON (P < 0.01). SL enhanced FTP by +5.5% vs. +1.2% in CON (P < 0.01). Comparable increases in 5-min peak power output (PPO) were observed between groups (P < 0.01) with +2.3% and +2.7% in SL and CON, respectively (P = 0.77). SL 1-min PPO was unchanged (+0.8%) whilst CON improved by +3.9% (P = 0.0144). CONCLUSION: Despite reduced relative training intensity, our data demonstrate short-term "sleep low-train low" intervention improves FTP compared with typically "normal" CHO availability during exercise. Importantly, training was completed unsupervised at home (during the COVID-19 pandemic), thus demonstrating the feasibility of completing a "sleep low-train low" protocol under non-laboratory conditions.

Recent Progress in Applicability of Exercise Immunology and Inflammation Research to Sports Nutrition.

This article focuses on how nutrition may help prevent and/or assist with recovery from the harmful effects of strenuous acute exercise and physical training (decreased immunity, organ injury, inflammation, oxidative stress, and fatigue), with a focus on nutritional supplements. First, the effects of ketogenic diets on metabolism and inflammation are considered. Second, the effects of various supplements on immune function are discussed, including antioxidant defense modulators (vitamin C, sulforaphane, taheebo), and inflammation reducers (colostrum and hyperimmunized milk). Third, how 3-hydroxy-3-methyl butyrate monohydrate (HMB) may offset muscle damage is reviewed. Fourth and finally, the relationship between exercise, nutrition and COVID-19 infection is briefly mentioned. While additional verification of the safety and efficacy of these supplements is still necessary, current evidence suggests that these supplements have potential applications for health promotion and disease prevention among athletes and more diverse populations.

Effects of endurance training on the expression of host proteins involved in SARS-CoV-2 cell entry in C57BL/6J mouse.

The coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is threatening people's lives and impacting their health. It is still unclear whether people engaged in physical activity are at an increased risk of SARS-CoV-2 infection and severe forms of COVID-19. In order to provide data to help answer this question, we, therefore, investigated the effects of endurance training on the levels of host proteins involved in SARS-CoV-2 infection in mice. Eight-week-old C57BL/6J mice were subjected to treadmill running (17-25 m/min, 60-90 min, 5 sessions/week, 8 weeks). After the intervention, the levels of angiotensin-converting enzyme 2 (ACE2; host receptor for SARS-CoV-2), transmembrane protease serine 2 (TMPRSS2; host protease priming fusion of SARS-CoV-2 to host cell membranes), FURIN (host protease that promotes binding of SARS-CoV-2 to host receptors), and Neuropilin-1 (host coreceptor for SARS-CoV-2) were measured in 10 organs that SARS-CoV-2 can infect (larynx, trachea, lung, heart, jejunum, ileum, colon, liver, kidney, and testis). Six organs (heart, lung, jejunum, liver, trachea, and ileum) showed changes in the levels of at least one of the proteins. Endurance training increased ACE2 levels in heart (+66.4%), lung (+37.1%), jejunum (+24.7%) and liver (+27.4%), and FURIN in liver (+17.9%) tissue. In contrast, endurance training decreased Neuropilin-1 levels in liver (-39.7%), trachea (-41.2%), and ileum (-39.7%), and TMPRSS2 in lung (-11.3%). Taken together, endurance training altered the levels of host proteins involved in SARS-CoV-2 cell entry in an organ-dependent manner.

Health-Related Physical Fitness and Activity in Homeschool: A Systematic Review With Implications for Return to Public School.

BACKGROUND: The purpose of this systematic review is to summarize what is known about health-related physical fitness (cardiovascular endurance, muscular strength and endurance, flexibility, and body composition) and physical activity among homeschool youth. Findings from this study have implications for all American youth as they return to public school from mandated schooling at home during the COVID-19 pandemic. METHODS: Database engines identified over 22,000 articles with 82 abstracts screened for further review. Of these, 18 full-text articles were additionally screened with 10 cross-sectional articles included in the final review. Articles were condensed into a standard review template and findings were summarized by topic. RESULTS: Cardiovascular endurance findings were inconsistent. Abdominal, but not upper body, muscular strength and endurance were significantly lower in homeschool students. There were no reports on flexibility. Body composition was generally healthy in homeschool students and no differences in physical activity were seen. CONCLUSIONS: Research on health-related physical fitness in homeschool youth is limited and descriptive. Further testing and potential remediation may be needed for cardiovascular endurance, muscular strength and endurance, and flexibility in homeschool youth and their public school counterparts as they return to campus. However, existing literature supports healthy body composition and physical activity in this population.

Measuring the Feasibility and Effectiveness of an Individualized Exercise Program Delivered Virtually to Cancer Survivors.

ABSTRACT: In the spring of 2020, we faced a global pandemic that resulted in social distancing limitations not previously experienced, forcing practitioners to adapt exercise programming to a virtual model. The purpose of this investigation was to measure the effectiveness of a virtual exercise oncology program in 491 participants undergoing antineoplastic therapy between March and June 2020. Each session was completed virtually with a certified exercise oncology trainer. Fitness and psychological parameters were measured preexercise and postexercise intervention. Overall, participants completed 4949 of 5892 prescribed exercise sessions. Patients saw increases in cardiovascular endurance (15.2%, P < 0.05), muscular endurance (18.2%, P < 0.05), flexibility (31.9%, P < 0.05), feelings of support (58.7%, P < 0.05), and quality of life (32.2%, P < 0.05), as well as decreases in loneliness (54%, P < 0.05) and fatigue (48.7%, P < 0.05). In light of our findings, we assert that virtual exercise training is a viable option in circumstances where in-person, individualized exercise training is not possible.

Effect of Online Training during the COVID-19 Quarantine on the Aerobic Capacity of Youth Soccer Players.

Motor abilities, such as endurance and the optimal level of physical activity, play a fundamental role in football as they are necessary to maintain the high effectiveness of the training process. The aim of this study was the observation of the trend of changes in the level of cardiorespiratory endurance of young football players in a one-year cycle overlapping with the COVID-19 lockdown and an assessment of the impact of the training intervention during home confinement. The participants of the study were 24 young football players. We analysed the results of the study in a one-year training cycle (lockdown from 11 March 2020 to 6 May 2020). The cardiorespiratory endurance was measured using the Multistage 20 m Shuttle Run test-Beep Test. A repeated measures analysis of variance was used in the study. Detailed comparisons were made using Tukey's HSD test. Statistically significant differences were noted in endurance in a one year cycle: F(5.115) = 22.65; p < 0.001; partial Eta-squared = 0.50. An increase in the level of endurance by mean = 179.17 m, SD ± 189.87 m was noted between T1 and T6. After the break caused by the COVID-19 restrictions, a decrease in the level of cardiorespiratory endurance was noted. Only after two training mesocycles was a significant increase in the mean value noted compared to the period before the pandemic (p < 0.05). With the negative impact of restrictions in mind, coaches and physiotherapists should exercise caution when planning training, taking into consideration the level of physical activity during the pandemic.

Impact of COVID-19 lockdown on endurance capacity of elite handball players.

BACKGROUND: The lockdown due to the Coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 has far-reaching consequences for professional sports in Germany. The aim of the present study was to investigate the impact of the eight-week lockdown on endurance capacity of elite male handball players. METHODS: Ten male athletes (192±8 cm and 96±6 kg) from the first German handball league participated in the study. The effects of training on shuttle run tests between period 1 (P1: pre-season to mid-season) and period 2 (P2: mid-season to time after lockdown) were compared. The maximum oxygen uptake (VO2max) was assessed using an incremental exercise test (IET) (July 2019 and May 2020). RESULTS: During the COVID-19 lockdown, the athletes completed an instructed home-based strength and endurance program (52/48). The training effects were found to be reduced after the 8-weeks of COVID-19 lockdown (period 2) as compared to period 1 (mean difference 249±248 m, P=0.005). There was no significant difference in the running distance (2358±430 m vs. 2400±362 m, respectively, P=0.70) after the lockdown as compared to the pre-seasonal performance. VO2max (46.6±5.1 vs. 49.4±7.0 mL/kg/min, respectively, P=0.12) and the power output (3.13±0.36 vs. 3.13±0.43 W/kg, respectively, P=1.0) also did not differ between pre-season and after COVID-19 lockdown. CONCLUSIONS: The COVID-19 lockdown led to a reduction in endurance capacity of elite handball players without team training, despite a home-based strength and endurance program. Supervision of individual home-based training is highly recommended to avoid inadequate implementation of the training.

Effects of the COVID-19 confinement period on physical conditions in young elite soccer players.

BACKGROUND: The rapid spread of the SARS-CoV-2 infection required general confinement measures reducing or even preventing sport practice, which was a risk of detraining in athletes. In adolescents, detraining is poorly known as well as its prevention by home-exercises. This article aimed to assess the effects of COVID-19 confinement on detraining in young high-level soccer players despite a multimodal training program conducted at home. METHODS: Twenty-five elite soccer players, aged 14, were included to perform physical exercises at home during the COVID-19 confinement. Two cardio-training sessions and two upper and lower limb muscle strengthening sessions were performed per week. The exercise program was monitored remotely via the web. Hooper, training and mental indexes allowed a psychological follow-up. The effect of COVID-19 confinement on aerobic capacity was measured using a pre- and postconfinement Yo-Yo Test. RESULTS: Out of the 25 adolescences who completed the exercises program, 19 performed the postconfinement Yo-Yo Test. The running distance decreased by 614+/-630 m (-25%) (P=0001) and the maximal running speed by 0.97+/-1 km/h (-5%) (P=0.001), confirming detraining. Hooper, training and mental indexes remained stable showing a well-supported home COVID-19 confinement. CONCLUSIONS: The 2-month period of strict home confinement due to the SARS-CoV-2 pandemic was responsible for a decrease of aerobic abilities in adolescent soccer players, despite a remotely monitored multimodal exercises program.

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.