Sports despite masks: no negative effects of FFP2 face masks on cardiopulmonary exercise capacity in children.

Face masks were recognized as one of the most effective ways to prevent the spread of the COVID-19 virus in adults. These benefits were extended to children and adolescents. However, the fear of negative consequences from wearing a face mask during physical exercise led to cancellations of physical education lessons. This further decreased the amount of physical activity available to children and adolescents during the pandemic. However, there is little published data on the potential adverse effects of wearing the most effective and partially mandatory FFP2/N95 face masks during PE or physical activity (PA) in this age. Even though the pandemic has been declared as passed by the WHO, the rise of a new pandemic and thus the use of face masks for limiting its spread is inevitable, so we need to be better prepared for alternative options to lockdown and limitation of PA in such a scenario. Twenty healthy children aged 8-10 years performed two identical cardiopulmonary exercise tests as an incremental step test on a treadmill within an interval of 2 weeks, one time without wearing a protective mask and one time wearing an FFP2 mask. The cardiopulmonary exercise parameter and especially the end-expiratory gas exchange for oxygen and carbon dioxide (petO2 and petCO2) were documented for each step, at rest and 1 min after reaching physical exhaustion. Twelve boys (mean age 8.5 ± 1.4 years) and 8 girls (mean age 8.8 ± 1.4 years) showed no adverse events until maximal exertion. The mean parameters measured at peak exercise did not differ significantly between both examinations (mean peak VO2 = 42.7 ± 9.5 vs 47.8 ± 12.9 ml/min/kg, p = 0.097, mean O2pulse 7.84 ± 1.9 ml/min vs. 6.89 ± 1.8, p = 0.064, mean VE/VCO2slope 33.4 ± 5.9 vs. 34.0 ± 5.3, p = 0.689). The only significant difference was the respiratory exchange rate (RER, 1.01 ± 0.08 vs 0.95 ± 0.08, p = 0.004). The measured respiratory gases (end-tidal O2 and CO2) decreased and respectively increased significantly in almost every step when wearing an FFP2 mask. However, these levels were well below hypercapnia and above hypoxia. CONCLUSION:  In this study, no significant differences in the cardiorespiratory function at peak exercise could be discerned when wearing an FFP2/N95 face mask. While the end-tidal values for CO2 increased significantly and the end-tidal values for O2 decreased significantly, these values did never reach levels of hypercapnia or hypoxia. Furthermore, the children terminated the exercise at a lower RER and heart rate (HR) suggesting a subconscious awareness of the higher strain. Since the detrimental effects of limiting sports during the pandemic are well documented, stopping PE lessons altogether because of the minor physiological effects of wearing these masks instead of simply stopping pushing children to perform at their best seems premature and should be reconsidered in the future. WHAT IS KNOWN: • Wearing a face mask has an influence on psychological, social, and physiological functions in adults. • Because of the observed effects of wearing face masks in adults, physical activity in children was limited during the pandemic. WHAT IS NEW: • Wearing an FFP2/N95 mask during physical activity did not lead to hypercapnia or hypoxia in children in this study. • Even though end-tidal CO2 values were significantly higher and end-tidal O2 values significantly lower when wearing an FFP2/N95 face mask, no pathological values were reached.

High-Intensity Interval Training Programs Versus Moderate-Intensity Continuous Training for Individuals With Heart Failure: A Systematic Review and Meta-analysis.

OBJECTIVE: To explore the effect sizes of different high-intensity interval training (HIIT) protocols on cardiorespiratory parameters when compared with moderate-intensity continuous training (MICT) in different heart failure (HF) subtypes. DATA SOURCES: Electronic databases were searched from their inception date until January 23, 2023. STUDY SELECTION: Randomized controlled trials (RCTs) were included if they compared HIIT with MICT in patients with HF. The primary outcome was peak oxygen consumption (Vo2peak). Two reviewers independently evaluated 99 initially identified studies, resulting in the selection of 15 RCTs that met the eligibility criteria. DATA EXTRACTION: Data were extracted independently by 2 observers using a data extraction form drafted based on the CONSORT statement and the Template for Intervention Description and Replication; the methodological quality of the studies was analyzed individually based on the Tool for the Assessment of Study Quality in Exercise scale. DATA SYNTHESIS: Fifteen RCTs with 553 patients with HF were included in the systematic review. The included studies had moderate to good overall methodological quality. The results showed that HIIT was generally more effective than MICT at improving Vo2peak in patients with HF (n=541, 15 RCTs; MD: 1.49 mL/kg/min; I2=66%; P<.001). However, the effect size varied depending on the HF subtype and HIIT protocol used. For patients with HF with reduced ejection fraction (HFrEF), the long-interval (high-intensity interval lasting ≥4 min) and high-volume HIIT (high-intensity efforts in total ≥15 min) showed the largest benefits over the MICT (n=261, 6 RCTs; MD: 2.11 mL/kg/min; P<.001); followed by the short-interval (≤1 min) and high-volume HIIT (≥15 min; n=71, 3 RCTs; MD: 0.91 mL/kg/min; P=.12), and the short-interval and low-volume HIIT showed the least superiority over MICT (n=68, 3 RCTs; MD: 0.54 mL/kg/min; P=.05). For patients with HF with perceived ejection fraction, there was a modest beneficial effect from HIIT over MICT (n=141, 3 RCTs; MD: 0.55 mL/kg/min; P=.32). CONCLUSIONS: The long-interval and high-volume HIIT protocol may produce greater benefits than MICT for improving cardiopulmonary fitness in patients with HFrEF. Further research is needed to determine the optimal HIIT protocol for different HF subtypes and to provide definitive recommendations for clinical practice.

Cardiorespiratory fitness and submaximal exercise dynamics in normal-weight obesity and metabolically healthy obesity.

PURPOSE: Cardiorespiratory fitness (CRF) is critical for cardiovascular health. Normal-weight obesity (NWO) and metabolically healthy obesity (MHO) may be at increased risk for cardiovascular disease, but a comparison of CRF and submaximal exercise dynamics against rigorously defined low- and high-risk groups is lacking. METHODS: Four groups (N = 40; 10/group) based on body mass index (BMI), body fat %, and metabolic syndrome (MetS) risk factors were recruited: healthy controls (CON; BMI 18.5-24.9 kg/m2, body fat < 25% [M] or < 35% [F], 0-1 risk factors), NWO (BMI 18.5-24.9 kg/m2, body fat ≥ 25% [M] or ≥ 35% [F]), MHO (BMI > 30 kg/m2, body fat ≥ 25% [M] or ≥ 35% [F], 0-1 risk factors), or metabolically unhealthy obesity (MUO; BMI > 30 kg/m2, body fat ≥ 25% [M] or ≥ 35% [F], 2 + risk factors). All participants completed a V ˙ O2peak test on a cycle ergometer. RESULTS: V ˙ O2peak was similarly low in NWO (27.0 ± 4.8 mL/kg/min), MHO (25.4 ± 6.7 mL/kg/min) and MUO (24.6 ± 10.0 mL/kg/min) relative to CON (44.2 ± 11.0 mL/kg/min) when normalized to total body mass (p's < 0.01), and adjusting for fat mass or lean mass did not alter these results. This same differential V ˙ O2 pattern was apparent beginning at 25% of the exercise test (PGroup*Time < 0.01). CONCLUSIONS: NWO and MHO had similar peak and submaximal CRF to MUO, despite some favorable health traits. Our work adds clarity to the notion that excess adiposity hinders CRF across BMI categories. CLINICALTRIALS: gov registration: NCT05008952.

Associations among motor competence, health-related fitness, and physical activity in children: A comparison of gold standard and field-based measures.

This study compared the associations among motor competence, health-related fitness, and physical activity measured by gold standard and field-based methods in children. A total of 248 first-grade children (153 boys) aged 6-7 years participated in the study. Motor competence was assessed using the Test of Gross Motor Development, Second Edition (TGMD -2). Gold standard measures were percent body fat using dual-energy X-ray absorptiometry, peak oxygen uptake per weight using a gas analyser, and moderate-to-vigorous physical activity using accelerometers. Field-based measures were body mass index, maximum speed during progressive running on a treadmill, and a physical activity questionnaire. Multiple regression analysis adjusted for age and sex was used to examine the associations of motor competence with one of the health-related variables and compared differences by measurement method. The results indicated that field-based measures models showed lower associations (R2 = 0.02-0.17) than the gold standard (R2 = 0.21-0.27) and lower standardised regression coefficients for sex and motor competence, except for maximum speed. In conclusion, gold standard measures resulted in stronger associations between motor competence, and health-related fitness and physical activity in children. Examining the contribution of motor competence in children's health using field-based tests can underestimate it.

Cardiorespiratory fitness assessed with cardiopulmonary exercise testing in patients with juvenile idiopathic arthritis: a systematic review and meta-analysis.

OBJECTIVES: JIA is the most common type of arthritis in children and adolescents, causing joint damage, chronic pain and disability. Deconditioning is also prevalent in patients with JIA due to both inactivity and the disease progression, resulting in reduced cardiorespiratory fitness (CRF). We aimed to evaluate CRF of patients with JIA compared with healthy controls. METHODS: This is a systematic review and meta-analysis of studies using cardiopulmonary exercise testing (CPET) to examine differences in determinants of CRF between patients with JIA vs healthy controls. The primary outcome was peak oxygen uptake (VO2peak). Literature search involved PubMed, Web of Science and Scopus databases, manual search of article references and grey literature. Quality assessment was undertaken with Newcastle-Ottawa Scale. RESULTS: From 480 literature records initially retrieved, eight studies (538 participants) were included in final meta-analysis. VO2peak was significantly lower in patients with JIA compared with controls [weighted mean difference (WMD): -5.95 ml/kg/min (95% CI -9.26, -2.65)]. Exercise duration and VO2peak (% predicted) were found to be significantly impaired in patients with JIA compared with controls [standardized mean difference: -0.67 (95% CI -1.04, -0.29) and WMD: -11.31% (95% CI -20.09, -2.53), respectively], while no significant differences were found in maximum heart rate. CONCLUSION: VO2peak and other CPET variables were lower in patients with JIA compared with controls, indicating reduced CRF in the former. Overall, exercise programs for patients with JIA should be promoted as part of their treatment to improve physical fitness and reduce muscle atrophy. PROSPERO REGISTRATION: CRD42022380833.

Moderate Continuous and Modified High-Intensity Interval Training in Patients With Left Ventricular Assist Devices: The Prospective Train-the-LVAD Trial.

BACKGROUND: High-intensity interval training (HIIT) of 4 minutes at 80%-90% of peak oxygen consumption (VO2peak) has been shown to be feasible in patients with left ventricular assist devices (LVADs). The effect of shorter bouts of HIIT, which reduce the anaerobic burden, has not been investigated compared to moderate continuous training (MCT). METHODS AND RESULTS: We conducted a prospective, monocentric study (NCT05121077) randomizing patients with LVADs into 20 minutes of MCT (n = 10) or short bouts (≤ 90 seconds) of HIIT (n = 10) following cardiopulmonary exercise testing at 50%-60% and 80%-90% of VO2peak. Each of the 18 supervised sessions (3×/week, t0-t1) included 10 minutes of strengthening training. The primary outcome was the increase of VO2peak in the 2 groups between t0 and t1. Secondary outcomes were changes in the 12-item Kansas City Cardiomyopathy Questionnaire, the 6-minute walk distance and the percentage of VO2peak at the first ventilatory threshold. VO2peak significantly increased with HIIT (13.0 ± 4.6mL/kg/min vs 14.6 ± 4.3mL/kg/min; P = 0.037), but not with MCT (11.8 ± 3.3mL/kg/min vs 13.1 ± 3.3mL/kg/min; P = 0.322), without between-group differences (P = 0.853). Secondary outcomes improved from t0-t1 in MCT and HIIT, without differences between the groups. CONCLUSIONS: Short bouts of HIIT are feasible, and they improved VO2peak and functional parameters in patients in this pilot prospective study.

Creatine supplementation and VO2max: a systematic review and meta-analysis.

Although creatine supplementation is well-known to increase exercise performance in acute high-intensity exercises, its role in aerobic performance based on VO2max is more controversial. Thus, we performed a systematic review and meta-analysis on the effects of creatine supplementation on VO2max. PubMed, Cochrane, Embase, and ScienceDirect were searched for randomized controlled trials (RCTs) reporting VO2max in creatine supplementation and placebo groups before and after supplementation. We computed a random-effects meta-analysis on VO2max at baseline, within groups following supplementation, on changes on VO2max between groups, and after supplementation between groups. Sensitivity analyses and meta-regression were conducted. We included 19 RCTs for a total of 424 individuals (mean age 30 years old, 82% men). VO2max did not differ at baseline between groups (creatine and placebo). Participants in both groups were engaged in exercise interventions in most studies (80%). Using changes in VO2max, VO2max increased in both groups but increased less after creatine supplementation than placebo (effect size [ES] = -0.32, 95%CI = -0.51 to -0.12, p = 0.002). Comparisons after creatine supplementation confirmed a lower VO2max in the creatine group compared to the placebo group (ES= -0.20, 95%CI = -0.39 to -0.001, p = 0.049). Meta-analysis after exclusion from meta-funnel resulted in similar outcomes in a subgroup of young and healthy participants. Meta-regressions on characteristics of supplementation, physical training, or sociodemographic were not statistically significant. Creatine supplementation has a negative effect on VO2max, regardless of the characteristics of training, supplementation, or population characteristics.Supplemental data for this article is available online at https://doi.org/10.1080/10408398.2021.2008864 .

Patients with Nonalcoholic Steatohepatitis and Advanced Liver Disease Have the Lowest Cardiorespiratory Fitness.

BACKGROUND & AIMS: Cardiorespiratory fitness and liver fibrosis are independently associated with poor outcomes in patients with nonalcoholic steatohepatitis (NASH), however, conflicting reports exist about their relationship. We aimed to better characterize the relationship between cardiorespiratory fitness and liver histology in a cross-sectional study of patients with biopsy-proven NASH. METHODS: Participants aged 18-75 years completed VO2peak fitness assessment using symptom-limited graded exercise testing. Participants were compared by liver fibrosis stage and NAFLD Activity Score (NAS). Multivariable models were constructed to assess factors related to relative VO2peak, including liver fibrosis and NAS. RESULTS: Thirty-five participants with mean age 48 ± 12 years and body mass index 33.5 ± 7.6 kg/m2 were enrolled. Seventy-four percent of participants were female and 49% had diabetes. A dose-dependent relationship was found between relative VO2peak and liver fibrosis. Relative VO2peak was significantly lower in participants with advanced fibrosis (F3 disease- 15.7 ± 5.3 vs. ≤ F2 disease- 20.7 ± 5.9 mL/kg/min, p = 0.027). NAS > 5 was also associated with lower relative VO2peak (22.6 ± 5.7 vs. 16.5 ± 5.1 mL/kg/min, p = 0.012) compared to NAS ≤ 5. With multivariable modeling, advanced fibrosis remained independently predictive of relative VO2peak while NAS trended towards significance. DISCUSSION AND CONCLUSIONS: Advanced liver fibrosis is independently associated with cardiorespiratory fitness in patients with NASH. This may explain the incremental increase in mortality as liver fibrosis stage increases. Further research is needed to determine if exercise training can improve cardiorespiratory fitness across multiple stages of liver fibrosis and directly reduce morbidity and mortality in patients with NASH.

Body composition, cardiorespiratory fitness, and neuromuscular adaptations induced by a home-based whole-body high intensity interval training.

Background/objective: Bodyweight exercises performed at home could be a complementary approach to improve health-related fitness in people having little spare time and during stay-at-home periods. This study then investigated body composition, cardiorespiratory fitness, and neuromuscular adaptations to a home-based, video-directed, whole-body high-intensity interval training (WB-HIIT). Methods: Fourteen subjects participated to an 8-week WB-HIIT (6 females, 23 ± 1 years) and fourteen were included in a non-exercise control group (CTL; 6 females, 24 ± 4 years). All took part to pre- and post-intervention assessments of body composition, peak oxygen uptake (VO2peak) and first ventilatory threshold (VT1; index of aerobic capacity), dynamic (leg press 3-repetition maximum) and isometric strength (knee extensors maximal isometric contractions with assessment of voluntary activation), and muscle endurance during an isometric submaximal contraction maintained till exhaustion. WB-HIIT consisted in 30-s all-out whole-body exercises interspaced with 30 s of active recovery. Training sessions were performed at home by means of videos with demonstration of exercises. Heart rate was monitored during sessions. Results: WB-HIIT increased VO2peak (5%), VT1 (20%), leg lean mass (3%), dynamic (13%) and isometric strength (6%), and muscle endurance (28%; p < 0.05), while they did not improve in CTL. VO2peak increase was correlated (r = 0.56; p < 0.05) with the time spent above 80% of maximal heart rate during training sessions. Isometric strength increase was correlated with change in voluntary activation (r = 0.74; p < 0.01). Conclusion: The home-based WB-HIIT induced concomitant cardiorespiratory fitness and neuromuscular improvements. The predominant effect was observed for aerobic capacity and muscle endurance which could improve exercise tolerance and reduce fatigability.

How do chronotype and sleep patterns impact young athletes' aerobic performance during Ramadan intermittent fasting?

Background: Ramadan observance has been practiced by many faith groups and cultures worldwide. Mo-reover, recently, it has been adopted as a natural alternative to promote public health. During Ramadan, our circadian rhythm can be altered. This study investigates how athletes' chronotype and sleep patterns impact aerobic fitness during Ramadan intermittent fasting. Study design: A prospective cohort design with repeated measurements was adopted. We measured the chronotype, maximal Oxygen Uptake as a measure of aerobic performance, and sleep patterns before and during Ramadan intermittent fasting. Then we explored the correlation among these variables. Methods: 50 amateur athletes (Mean age = 17.22 years SD = 1.15) from Morocco participated in this study. The maximal Oxygen Uptake was measured with the 20-m shuttle-run test. The chronotype was assessed by the Morningness-Eveningness Questionnaire. The sleep timing was assessed by Sleep Timing Question-naire. We also assessed sleep quality with the Pittsburgh Sleep Quality Index. We examined the difference between variable means before and during Ramadan, also considering chronotype and sleep patterns of participants. Results: The results showed a significant decrease in sleep quality and maximal Oxygen Uptake during the Ramadan Intermittent Fasting. Also, we found a significant correlation between the chronotype, time in bed and time spent asleep. However, chronotype and sleep quality did not affect maximal Oxygen Uptake during the Ramadan intermittent fasting. Conclusions: Sleep and chronotype do not influence physical performance during Ramadan Intermittent Fasting. More research is needed to identify the leading cause of the drop in aerobic performance.

Cardiopulmonary exercise testing in patients with end-stage kidney disease: principles, methodology and clinical applications of the optimal tool for exercise tolerance evaluation.

Chronic kidney disease (CKD), especially end-stage kidney disease (ESKD), is associated with an increased risk for cardiovascular events and all-cause mortality. Exercise intolerance as well as reduced cardiovascular reserve is extremely common in patients with CKD. Cardiopulmonary exercise testing (CPET) is a non-invasive, dynamic technique that provides an integrative evaluation of cardiovascular, pulmonary, neuropsychological and metabolic function during maximal or submaximal exercise, allowing the evaluation of functional reserves of these systems. This assessment is based on the principle that system failure typically occurs when the system is under stress and thus CPET is currently considered to be the gold standard for identifying exercise limitation and differentiating its causes. It has been widely used in several medical fields for risk stratification, clinical evaluation and other applications, but its use in everyday practice for CKD patients is scarce. This article describes the basic principles and methodology of CPET and provides an overview of important studies that utilized CPET in patients with ESKD, in an effort to increase awareness of CPET capabilities among practicing nephrologists.

Accuracy of exercise-based tests for estimating cardiorespiratory fitness and muscle strength in early-stage breast cancer survivors in Japan.

PURPOSE: We aimed to examine whether cardiorespiratory fitness and leg strength can be estimated based on their relationship with physical performance tests in Japanese breast cancer survivors. METHODS: Participants were 50 sedentary women aged 20 to 59 years who have received breast surgery in the past 2 to 13 months after diagnosis of invasive breast cancer (stage I-IIa). Cardiorespiratory fitness and leg strength were measured by peak oxygen consumption (VO2peak), and one-repetition maximum for leg press (leg press 1RM). Physical performance tests were performed 6-min walk test, chair stand test, and grip strength. Using multiple regression analysis, we developed prediction equations for VO2peak and leg strength based on their associations with the physical performance tests. The validity of the estimation equations was assessed using Bland-Altman plots. RESULTS: Mean age, VO2peak, and leg press 1RM were 48 ± 6 years, 25.0 ± 3.6 mL/kg/min, and 95 ± 32 kg, respectively. Multiple regression analysis yielded 6-min walk test distance, age, height, and body weight as predictors of VO2peak. Measured VO2peak and predicted VO2peak showed a moderate positive correlation (r = 0.463, p < 0.001). Chair stand test, grip strength, age, height, and body weight were selected as predictors of leg press 1RM. There was a strong positive correlation between predicted and measured leg press 1RM (r = 0.754, p < 0.001). CONCLUSION: The results suggest that leg strength can be predicted using physical performance tests. However, further examination may be needed to determine whether cardiorespiratory fitness can be predicted based on 6-min walk test.

A novel treadmill protocol for uphill running assessment: the incline incremental running test (IIRT).

This study aimed to compare the maximal and submaximal aerobic parameters between two incremental running tests, one being horizontal and the other an incline-based test, namely the incline incremental running test (IIRT). Twenty endurance-trained trail runners completed two incremental treadmill tests, until exhaustion. The first test was performed using an incline of 1%, with speed increments. Then, the IIRT was performed with the speed set at 50% of the peak speed obtained during the previous test, and the incline was incremented. Cardiorespiratory measurements and blood lactate concentration ([La]) were assessed. The mean peak workload from the horizontal test was 17.6 ± 1.4 km.h-1 and peak workload from IIRT was 17.3 ± 1.3% of incline. The VO2peak and [La]peak were not significantly different between the protocols. However, the HRpeak was significantly lower at IIRT. In conclusion, most of the maximal and submaximal aerobic indices showed no differences between the incremental tests analysed. The exceptions were the HRpeak and HR at the lactate turnpoints, that were lower, and the peak O2 pulse that was greater for the IIRT. Taken together, these data support the validity of the IIRT as a specific test for the physiological assessment of runners involved with uphill performances.

Assessment of Exercise Intolerance in Patients with Pre-Dialysis CKD with Cardiopulmonary Function Testing: Translation to Everyday Practice.

BACKGROUND: Chronic kidney disease (CKD) is often characterized by increased prevalence of cardiovascular risk factors and increased incidence of cardiovascular events and death. Reduced cardiovascular reserve and exercise intolerance are common in patients with CKD and are associated with adverse outcomes. SUMMARY: The gold standard for identifying exercise limitation is cardiopulmonary exercise testing (CPET). CPET provides an integrative evaluation of cardiovascular, pulmonary, hematopoietic, neuropsychological, and metabolic function during maximal or submaximal exercise. It is useful in clinical setting for differentiation of the causes of exercise intolerance, risk stratification, and assessment of response to relevant treatments. A number of recent studies have used CPET in patients with pre-dialysis CKD, aiming to assess the cardiovascular reserve of these individuals, as well as the effect of interventions such as exercise training programs on their functional capacity. This review provides an in-depth description of CPET methodology and an overview of studies that utilized CPET technology to assess cardiovascular reserve in patients with pre-dialysis CKD. Key Messages: CPET can delineate multisystem changes and offer comprehensive phenotyping of factors determining overall cardiovascular risk. Potential clinical applications of CPET in CKD patients range from objective diagnosis of exercise intolerance to preoperative and long-term risk stratification and providing intermediate endpoints for clinical trials. Future studies should delineate the association of CPET indexes, with cardiovascular and respiratory alterations and hard outcomes in CKD patients, to enhance its diagnostic and prognostic utility in this population.

A randomized controlled trial of a structured exercise intervention after the completion of acute cancer treatment in adolescents and young adults.

BACKGROUND: Cancer treatments are frequently associated with impaired physical fitness, quality of life (QOL), and fatigue, often persisting into survivorship.  Studies in older adults with cancer have demonstrated benefits from exercise; however, this has not been rigorously investigated in adolescents and young adults (AYA). The aim of this study was to determine whether a structured 10-week exercise intervention was associated with improved cardiorespiratory fitness (VO2peak ), fatigue, and QOL in AYA who have recently completed cancer treatment. METHOD: Forty-three AYA (median age 21 ± 6 years) were randomly assigned to an exercise group (n = 22) or a control group (n = 21). The exercise group received a structured 10-week exercise program comprising progressive aerobic and resistance exercise; the control arm received routine care. VO2peak was measured at baseline, 10 weeks, and six months. Fatigue and QOL were assessed by the FACIT fatigue scale and the PEDS QL, respectively. RESULTS: Mean VO2peak at baseline was 26.5 ± 7.2 mL.kg-1 .min-1 , which is substantially lower than population norms. The exercise group demonstrated significant improvement in VO2peak at 10 weeks compared with controls (33.8 ± 8.1 vs 29.6 ± 7.6 mL.kg-1 .min-1 , P = 0.0002), but by six months, the difference was no longer significant (32.9 ± 7.0 vs 30.9 ± 11.0 mL.kg-1 .min-1 , P = 0.21). There were no significant differences in fatigue or total QOL scores between groups. CONCLUSION: Cancer treatment is associated with reduced VO2peak in AYA. Improvement in VO2peak was accelerated by a 10-week exercise program; however, no significant benefit was observed in QOL or fatigue. The plateau in VO2peak at six months suggests that a maintenance exercise program may be beneficial.

Additional cardiovascular fitness when progressing from moderate- to high-intensity exercise training in previously trained breast cancer survivors.

PURPOSE: Cardiovascular disease, often secondary to chemotherapy, is the leading cause of death in BC survivors. Increased aerobic capacity improves post-rehabilitation survival; however, many cancer rehabilitation programs are limited to lower intensity training. High-intensity interval training (HIIT) is associated with the largest improvements in aerobic capacity; therefore, this study aimed to determine whether HIIT would cause a greater increase in VO2peak than continuous moderate-intensity (MICT) exercise in previously trained BC survivors. METHODS: Twenty BC survivors who had completed a low/moderate-intensity exercise rehabilitation program performed a VO2peak test and received a dual-energy X-ray absorptiometry (DXA) scan at baseline and after randomization into a 12-week HIIT or MICT program. ANOVA with repeated measures determined the effects of the different training programs on aerobic capacity and body composition. RESULTS: Both groups began the training program near or above age- and sex-matched VO2peak norms. Pre- to post-intervention improvements in VO2peak (P = 0.006) and waist circumference (P = 0.007) were found in both groups; however, there were no between-group differences. Minute ventilation and peak workload increased in the HIIT group (P < 0.05) but not the MICT group. Body composition was not different after either training program. CONCLUSIONS: These data suggest that transitioning from low/moderate-intensity exercise to moderate/high-intensity exercise causes further clinically relevant increases in VO2peak in previously trained BC survivors. HIIT did not cause a significantly greater improvement in VO2peak than MICT; however, future studies with greater intensity and frequency of training are encouraged.

Aerobic fitness and sympathetic responses to spontaneous muscle sympathetic nerve activity in young males.

PURPOSE: Lower aerobic fitness increases the risk of developing hypertension. Muscle sympathetic nerve activity (MSNA) is important for the beat-by-beat regulation of blood pressure. Whether the cardiovascular consequences of lower aerobic fitness are due to augmented transduction of MSNA into vascular responses is unclear. We tested the hypothesis that aerobic fitness is inversely related to peak increases in total peripheral resistance (TPR) and mean arterial pressure (MAP) in response to spontaneous MSNA bursts in young males. METHODS: Relative peak oxygen consumption (VO2peak, indirect calorimetry) was assessed in 18 young males (23 ± 3 years; 41 ± 8 ml/kg/min). MSNA (microneurography), cardiac intervals (electrocardiogram) and arterial pressure (finger photoplethysmography) were recorded continuously during supine rest. Stroke volume and cardiac output (CO) were estimated via the ModelFlow method. TPR was calculated as MAP/CO. Changes in TPR and MAP were tracked for 12 cardiac cycles following heartbeats associated with or without spontaneous bursts of MSNA. RESULTS: Overall, aerobic fitness was inversely correlated to the peak ΔTPR (0.8 ± 0.7 mmHg/l/min; R = - 0.61, P = 0.007) and ΔMAP (2.3 ± 0.8 mmHg; R = - 0.69, P < 0.001), but not with the peak ΔCO (0.2 ± 0.1 l/min; P = 0.50), MSNA burst frequency (14 ± 5 bursts/min; P = 0.43) or MSNA relative burst amplitude (65 ± 12%; P = 0.13). Heartbeats without an associated burst of MSNA did not increase TPR, MAP or CO. CONCLUSION: Although unrelated to traditional MSNA characteristics, aerobic fitness was inversely associated with spontaneous sympathetic neurovascular transduction in young males. This may be a potential mechanism by which aerobic fitness modulates the regulation of arterial blood pressure through the sympathetic nervous system.

Bicycle spiroergometry: comparison of standardized examination protocols for adolescents: is it necessary to define own standard values for each protocol?

PURPOSE: To compare performance data of adolescents collected with five different bicycle spiroergometry protocols and to assess the necessity for establishing standard values for each protocol. METHODS: One-hundred-twenty adolescents completed two bicycle spiroergometries within 14 days. One of the two tests was performed based on our institutional weight-adapted protocol (P0). The other test was performed based on one out of four exercise protocols widely used for children and adolescents (P1, 2, 3 or 4) with 30 persons each. The two tests were performed in a random order. Routine parameters of cardiopulmonary exercise tests (CPET) such as VO2peak, maximum power, O2 pulse, OUES, VE/VCO2 slope as well as ventilatory and lactate thresholds were investigated. Agreement between protocols was evaluated by Bland-Altman analysis, coefficients of variation (CV) and intra-class correlation coefficients (ICC). RESULTS: None of the CPET parameters were significantly different between P0 and P1, 2, 3 or 4. For most of the parameters, low biases between P0 and P1-P4 were found and 95% confidence intervalls were narrow. CV and ICC values largely corresponded to well-defined analytical goals (CV < 10% and ICC > 0.9). Only maximal power (Pmax) showed differences in size and drift of the bias depending on the length of the step duration of the protocols. CONCLUSION: Comparability between examination protocols has been shown for CPET parameters independent on step duration. Protocol-dependent standard values do not appear to be necessary. Only Pmax is dependent on the step duration, but in most cases, this has no significant influence on the fitness assessment.

Interrelationship of physical exercise, perceptual discrimination and academic achievement variables in high school students.

BACKGROUND: Many studies results suggest how can we improve the academic performance for our kids. The purposes of this study were to examine how physical activity could affect both academic achievement and fluid intelligence in adolescence. STUDY DESIGN: We measured the three variables (physical, cognitive, academic) and try to find the correlations between them. METHODS: A total of 167 adolescents (mean age = 16.34 years SD = 1.2) from Morocco are participating in this study. The cardiorespiratory fitness was measured with the20 m endurance shuttle-run test. We also assessed the Resistance capacity with 500m sprint test. The academic achievement was assessed by school grades. The fluid intelligence was assessed by using Raven's Standard Progressive Matrices. We examined the correlation between all variables. RESULTS: This study indicates that the academic achievement was positively associated with the Fluid Intelligence and also with the Resistance Capacity and not with Cardiorespiratory Fitness (VO2peak). CONCLUSIONS: We can conclude that the professionals and researchers in sports and education have to promote physical activity at the school age for a public health purpose.

Increasing Iron Status through Dietary Supplementation in Iron-Depleted, Sedentary Women Increases Endurance Performance at Both Near-Maximal and Submaximal Exercise Intensities.

BACKGROUND: Iron deficiency persists as the most common micronutrient deficiency globally, despite having known detrimental effects on physical performance. Although iron supplementation and aerobic exercise have been examined individually and are known to improve physical performance, the impact of simultaneous iron supplementation and aerobic training remains unclear. OBJECTIVE: The aim of this study was to examine the individual and combined effects of iron supplementation and aerobic training on improving maximal and submaximal physical performance in iron-depleted, nonanemic (IDNA) women. We hypothesized that women receiving iron would improve their endurance performance but not their estimated maximal oxygen consumption (eVO2max). METHODS: Seventy-three sedentary, previously untrained IDNA (serum ferritin <25 µg/L and hemoglobin >110 g/L) women aged 18-26 y with a body mass index (kg/m2) of 17-25 participated in a double-blind, 8-wk, randomized controlled trial with a 2 × 2 factorial design including iron supplementation (42 mg elemental Fe/d) or placebo and aerobic exercise training (5 d/wk for 25 min at 75-85% of age-predicted maximum heart rate) or no training. Linear models were used to examine relations between training, supplement, and changes in the primary outcomes of observed maximal oxygen consumption (VO2peak) and eVO2max and ventilatory threshold (absolute oxygen consumption and percentage of maximum). Re-evaluation of a published meta-analysis was used to compare effects of iron supplementation on maximal oxygen consumption (VO2max) and VO2peak. RESULTS: There were significant training-by-supplement interactions for VO2peak, volume of oxygen consumption at the ventilatory threshold, and the percentage of eVO2max where the threshold occurred, with the iron-untrained group performing better than the placebo-untrained group. There was no beneficial effect of iron supplementation for VO2max (mean difference: 0.53; 95% CI: -0.75, 1.81; P = 0.42), but a significant benefit was observed for VO2peak (mean difference: 1.87; 95% CI: 0.15, 3.60; P = 0.03). CONCLUSIONS: Iron supplementation increases endurance performance at submaximal and maximal (VO2peak) exercise intensities in IDNA women. However, increasing iron status does not increase eVO2max. This trial was registered at clinicaltrials.gov as NCT03002090.