Absolute VO2max Research Articles

Exercise volume and aerobic fitness in young adults: the Midwest Exercise Trial-2.

To examine the effect of exercise volume at a fixed intensity on changes in aerobic fitness. Ninety-two overweight/obese individuals (BMI 25–40 kg m2), age 18–30 years, 50 % women, completed a 10 mo, 5 d wk−1 supervised exercise intervention at 2 levels of exercise energy expenditure (400 or 600 kcal session−1) at 70–80 % heart rate (HR) max. Exercise consisted primarily of walking/jogging on motor-driven treadmills. The duration and intensity of all exercise sessions were verified by a downloadable HR monitor set to collect HR in 1-min epochs. All participants were instructed to continue their typical patterns of non-exercise physical activity and dietary intake over the duration of the 10 mo intervention. Maximal aerobic capacity (indirect calorimetry) was assessed on a motor-driven treadmill using a modified Balke protocol at baseline, mid-point (5 mo), and following completion of the 10 mo intervention. VO2 max (L min−1) increased significantly in both the 400 (11.3 %) and 600 kcal session−1 groups (14 %) compared to control (−2.0 %; p < 0.001); however, the differences between exercise groups were not significant. Similar results were noted for change in relative VO2 max (mL kg−1 min−1); however, the magnitude of change was greater than for absolute VO2 max (L min−1) (400 group = 18.3 %; 600 group = 20.2 %) due to loss of body weight over the 10-mo intervention in both exercise groups. Our results indicate that exercise volume was not associated with change in aerobic fitness in a sample of previously sedentary, overweight and obese young adults.

Interdisciplinary therapy improves cardiorespiratory fitness and inflammatory markers in obese adult women

IntroductionObesity is associated with an imbalance in cytokine concentrations, characterizing a low-grade chronic inflammatory status. The cardiorespiratory fitness is an important parameter that influences this inflammatory status, being a powerful predictor of early mortality. The interdisciplinary therapy has emerged as an alternative to prevent and treat obesity by improving health parameters. The aim of this study was to examine the effect of an interdisciplinary therapy on inflammatory markers and cardiorespiratory fitness in obese adult women. MethodsA total of twenty-eight (n = 28) adult women (age 43.3 ± 5.5 years and BMI 34.9 ± 3.1 kg/m2) completed 20 weeks of interdisciplinary therapy involving physical exercise, nutritional and psychological support at Obesity Study Group in Federal University of São Paulo, Santos – Brazil. The cardiorespiratory fitness was measured through a maximal cycle-ergometer test. The inflammatory markers analyzed were leptin, TNF-α, MCP-1 and adiponectin. ResultsImprovement in leptin (Δ −25.7% p < 0.001), MCP-1 (Δ −12.6% p < 0.001), relative VO2Max (Δ +15.4%, p = 0.001) and absolute VO2Max (Δ +10.8%, p = 0.001) were observed after the interdisciplinary therapy. In addition, a relevant negative correlation (r = −0.45, p = 0.021) was found between leptin level and cardiorespiratory fitness. ConclusionThe interdisciplinary therapy showed a significant positive effect on leptin and MCP-1 levels, cardiorespiratory fitness and metabolic profile. The therapy also showed an important negative correlation between leptin and cardiorespiratory fitness. These results suggest that the proposed methodology can be effective to treat obesity by increasing aerobic fitness and reducing proinflammatory pathways. Clinical Trial Registration NumberNCT02573688.

Increased post-operative cardiopulmonary fitness in gastric bypass patients is explained by weight loss.

Roux-en-Y gastric bypass (RYGB) leads to a major weight loss in obese patients. However, given that most patients remain obese after the weight loss, regular exercise should be part of a healthier lifestyle. The primary aim of this study was to investigate the cardiopulmonary fitness in obese patients before and after RYGB. Thirty-four patients had body composition and cardiopulmonary fitness (VO2max ) assessed and completed questionnaires regarding physical activity and function twice before RYGB (time points A and B) and 4 and 18 months after surgery (time points C and D). Weight loss was 37 ± 2 kg during the study period. VO2max increased (A: 21 ± 1 vs D: 29 mL/min/kg, P < 0.001), but absolute VO2max decreased (A: 2713 ± 126 vs 2609 ± 187 mL/min, P = 0.02) and VO2max per kilogram fat free mass did not change. Self-perceived limitations to perform exercise decreased and self-perceived physical fitness increased after RYGB. Self-reported low- and high-intensity physical activity did not change. With weight loss, self-rated fitness level increased and the limitations to perform exercise decreased in RYGB patients. Nevertheless, as shown by the lower absolute VO2max , RYGB patients do not adopt new exercise habits following surgery.

Guidelines to Classify Female Subject Groups in Sport-Science Research

To review current cycling-related sport-science literature to formulate guidelines to classify female subject groups and to compare this classification system for female subject groups with the classification system for male subject groups. A database of 82 papers that described female subject groups containing information on preexperimental maximal cycle-protocol designs, terminology, biometrical and physiological parameters, and cycling experience was analyzed. Subject groups were divided into performance levels (PLs), according to the nomenclature. Body mass, body-mass index, maximal oxygen consumption (VO2max), peak power output (PPO), and training status were compared between PLs and between female and male PLs. Five female PLs were defined, representing untrained, active, trained, well-trained, and professional female subjects. VO2max and PPO significantly increased with PL, except for PL3 and PL4 (P < .01). For each PL, significant differences were observed in absolute and relative VO2max and PPO between male and female subject groups. Relative VO2max is the most cited parameter for female subject groups and is proposed as the principal parameter to classify the groups. This systematic review shows the large variety in the description of female subject groups in the existing literature. The authors propose a standardized preexperimental testing protocol and guidelines to classify female subject groups into 5 PLs based on relative VO2max, relative PPO, training status, absolute VO2max, and absolute PPO.

Male Fat Patterning Negatively Correlates With Cardiorespiratory Fitness Even In A Highly Athletic Population

Body fatness has been shown to correlate with lower aerobic performance in athletic populations. Few studies have quantified this relationship using the gold standard body composition measure, dual energy x-ray absorptiometry (DEXA), in combination with direct maximal aerobic capacity (VO2max) measurement. More valid data is needed for training to target body composition aimed at enhancing aerobic performance. PURPOSE: The purpose of this study was to assess the relationship between cardiorespiratory fitness (CRF), indicated through VO2max, and DEXA percent body fat in an athletic college aged (20-29 yrs) population. METHODS: 12 males (mean ± sd; age, 22.25 ± 2.18 yrs) were assessed for body composition (DEXA) and VO2max (graded treadmill protocol with indirect calorimetry). Pearson product moment correlation coefficients (r; p ≤ 0.05 for significance) were calculated for relative (mL O2/kg/min) and absolute (L O2/min) VO2max vs. total body % fat, android % fat, gynoid % fat, trunk % fat, leg % fat, android to gynoid % fat ratio, and trunk to leg % fat ratios. RESULTS: Subjects were primarily fit with respect to CRF as all subjects (mean ± sd; VO2max, 50.91 ± 7.89), with the exception of 3 individuals who were above average, exhibited age-matched excellent VO2max. Significant negative Pearson product moment correlations were found between relative VO2max with total % body fat (r -0.62, p 0.03), android % body fat (r - 0.64, p 0.02), gynoid % body fat (r -0.58, p 0.05), and trunk % body fat (r -0.66, p 0.02) and absolute VO2max with android to gynoid % fat ratios (r -0.65, p 0.02) and trunk to leg % fat ratios (r -0.71, p 0.01) CONCLUSION: Total and compartmental % body fat, with special emphasis on trunk and android fat representing visceral fat, were significantly negatively correlated with CRF in an aerobically fit college male population. Male visceral fat distribution showing the most significant inverse correlations with CRF suggests typical male fat patterning inhibits VO2max even in aerobically fit men. Findings of this study may shed light on the need for examination of specific training methods to improve male aerobic performance via targeted reduction of visceral fat.

Maximal aerobic capacity in the winter-Olympics endurance disciplines: Olympic-medal benchmarks for the time period 1990-2013.

To generate updated Olympic-medal benchmarks for VO2max in winter endurance disciplines, examine possible differences in VO2max between medalists and nonmedalists, and calculate gender difference in V˙ O2max based on a homogeneous subset of world-leading endurance athletes. The authors identified 111 athletes who participated in winter Olympic Games/World Championships in the period 1990 to 2013. All identified athletes tested VO2max at the Norwegian Olympic Training Center within ±1 y of their championship performance. Testing procedures were consistent throughout the entire period. For medal-winning athletes, the following relative VO2max values (mean:95% confidence intervals) for men/women were observed (mL · min-1 · kg-1): 84:87-81/72:77-68 for cross-country distance skiing, 78:81-75/68:73-64 for cross-country sprint skiing, 81:84-78/67:73-61 for biathlon, and 77:80-75 for Nordic combined (men only). Similar benchmarks for absolute VO2max (L/min) in male/female athletes are 6.4:6.1-6.7/4.3:4.1-4.5 for cross-country distance skiers, 6.3:5.8-6.8/4.0:3.7-4.3 for cross-country sprint skiers, 6.2:5.7-6.4/4.0:3.7-4.3 for biathletes, and 5.3:5.0-5.5 for Nordic combined (men only). The difference in relative VO2max between medalists and nonmedalists was large for Nordic combined, moderate for cross-country distance and biathlon, and small/trivial for the other disciplines. Corresponding differences in absolute VO2max were small/trivial for all disciplines. Male cross-country medalists achieve 15% higher relative VO2max than corresponding women. This study provides updated benchmark VO2max values for Olympic-medal-level performance in winter endurance disciplines and can serve as a guideline of the requirements for future elite athletes.

The feasibility and effectiveness of high-intensity boxing training versus moderate-intensity brisk walking in adults with abdominal obesity: a pilot study.

BackgroundHigh-intensity interval training (HIIT) performed on exercise cycle or treadmill is considered safe and often more beneficial for fat loss and cardiometabolic health than moderate-intensity continuous training (MICT). The aim of this pilot study was to assess the feasibility and effectiveness of a 12-week boxing training (HIIT) intervention compared with an equivalent dose of brisk walking (MICT) in obese adults.MethodsMen and women with abdominal obesity and body mass index >25 kg/m2 were randomized to either a boxing group or a brisk walking (control) group for 12 weeks. Each group engaged in 4 training sessions per week, equated for total physical activity. Feasibility outcomes included recruitment rates, assessment of training intensities, adherence and adverse events. Effectiveness was assessed pre and post intervention via pertinent obesity-, cardiovascular-, and health-related quality of life (HRQoL) outcomes.ResultsNineteen individuals expressed an interest and 63% (n = 12) consented. Recruitment was slower than anticipated (1.3 participants/week). The boxing group trained at a significantly higher intensity each week versus the brisk walking group (p < 0.05). Two participants in the boxing group experienced an adverse event; both continued to exercise with modifications to the exercise program. No other adverse events were noted. The boxing group attended more sessions (79% vs. 55%) and had a lower attrition rate (n = 0 vs. n = 2) than the walking group. Analysis of covariance revealed that the boxing group significantly improved body fat percentage (p = 0.047), systolic blood pressure (p = 0.026), augmentation index (AIx; p < 0.001), absolute VO2max (p = 0.015), and Physical Functioning (p = 0.042) and Vitality (p = 0.024) domains of HRQoL over time. The walking group did not improve any clinical outcomes, and experienced a worsening of Vitality (p = 0.043).ConclusionsBoxing training (HIIT) in adults with abdominal obesity is feasible and may elicit a better therapeutic effect on obesity, cardiovascular, and HRQoL outcomes than an equivalent dose of brisk walking (MICT). Robustly designed randomized controlled trials are required to confirm these findings and inform clinical guidelines and practice for obesity treatment.Trial registrationTrial registration: ACTRN12615000007538

THE GSTP1 c.313A>G POLYMORPHISM MODULATES THE CARDIORESPIRATORY RESPONSE TO AEROBIC TRAINING.

The GSTP1 c.313A>G polymorphism is a candidate to explain some of the individual differences in cardiorespiratory fitness phenotypes’ responses to aerobic exercise training. We aim to explore the association between the GSTP1 c.313A>G polymorphism and the response to low-high impact aerobic exercise training. Sixty-six Polish Caucasian women were genotyped for the GSTP1 c.313A>G polymorphism; 62 of them completed 12-week aerobic (50-75% HRmax) exercise training and were measured for selected somatic features (body mass and BMI) and cardiorespiratory fitness indices – maximal oxygen uptake (VO2max, maximum heart rate (HRmax), maximum ventilation (VEmax) and anaerobic threshold (AT) – before and after the training period. Two-factor analysis of variance revealed a main training effect for body mass reduction (p=0.007) and BMI reduction (p=0.013), improvements of absolute and relative VO2max (both p<0.001), and increased VEmax (p=0.005), but not for changes in fat-free mass (FFM) (p=0.162). However, a significant training x GSTP1 c.313A>G interaction was found only for FFM (p=0.042), absolute and relative VO2max (p=0.029 and p=0.026), and VEmax (p=0.005). As the result of training, significantly greater improvements in VO2max, VEmax and FFM were gained by the GG+GA group compared to the AA genotype group. The results support the hypothesis that heterogeneity in individual response to training stimuli is at least in part determined by genetics, and GSTP1 c.313A>G may be considered as one (of what appear to be many) target polymorphisms to influence these changes.

Comparison of physiological and perceptual responses to a maximal exhaustive test performed on the SRM and the Cyclus2 ergometer

Background: No cycle ergometer perfectly replicates the physiological demands and movement patterns associated with real world cycling (Abbiss et al., 2009: International Journal of Sports Medicine, 30(2), 107-112). The purpose of this research was to compare physiological and perceptual responses during a standardized exercise test using the classical SRM ergometer (Schoberer Rad Messtechnik, GmbH, JA¼lich, Germany) and the Cyclus2 ergometer (RBM elektronik-automation GmbH, Leipzig, Germany) which allows the use of personal bikes and allows lateral movement. Methods: 13 moderately trained cyclists (mean ± SD: age 35 ± 7 years, body mass 74.1 ± 9.6 kg) performed two graded cycling tests to volitional exhaustion in a randomized order on the SRM and the Cyclus2 ergometer. Maximal aerobic capacity (VO2max), maximal aerobic power (MAP), blood lactate concentrations and heart rate responses were compared using a paired t-test. Participants were also required to fill in the NASA Task Load Index (TLX) questionnaire (Hart, 2006: NASA-Task Load Index, 50th Human Factors and Ergonomics Society Meeting, Santa Monica, USA) after each test to assess the perceived workload in an effort to understand if one ergometer is perceived to be more or less of a workload than its counterpart. In order to analyse the workload from each participant, individual TXL factors were summed for each ergometer TLX administration creating an overall workload score per ergometer. After conclusion of the experiment participants were asked to state their preference in ergometers. Lastly, a correlation was performed on the level of performance within the ergometer testing and the perceived performance. Results: Compared physiological responses and MAP (321 ± 44 W; SRM and 326 ± 41 W; Cyclus2) did not find any significant differences. A constructed ANOVA model which examined the difference of the overall workload scores between the two ergometers did not show any significant difference (F(1,12) = .025, p = .876). In order to examine if there were individual factor differences between the six TLX factors of each ergometer, a constructed repeated measure MANOVA did not reveal any significant differences between ergometers and within individual TLX scores (F(5,8) = .995, p = .477). Interestingly, the absolute VO2max performance score was significantly correlated on the Cyclus2 ergometer with the self-reported performance TLX factor (r = .560, p = .047) while the same score was not significant for the SRM ergometer (r = .247, p = .415). However, participants were highly positively correlated between perceived performance on each ergometer (r = .736, p = .004). Participants were asked to name which ergometer they felt they performed better on. Eight participants named the SRM Ergometer, while 5 named the Cyclus2. When asked which ergometer they preferred to use, 4 named the SRM Ergometer, while 9 named the Cyclus2. When asked which ergometer the participant would prefer to use if the test were to be run again, 5 named the SRM Ergometer, while 8 named the Cyclus2. Participants were lastly asked to think of how comfortable they were for each of the ergometers. A paired t-test examined the differences between the comfort ratings of revealed a significant difference (t = -2.803, p = .016), with this being driven by the higher favourable ratings of the Cyclus2 compared to the SRM (Figure 1). These differences can be accounted for by 6 participants stating that they preferred the Cyclus2 and increased comfort owning to the usage of their own bike. Those that preferred the SRM stated it was more solid and stable (n = 4). Discussion: Biomechanical factors can influence physiological responses, perception of exercise and efficiency of an individual riding a bicycle or ergometer at a given power output (Patterson and Moreno, 1990: Medicine & Science in Sports & Exercise, 22(4), 512-516. Whilst not demonstrating any differences in physiological variables and MAP, participants generally felt more comfortable on the ergometer, which allows the use of personal bikes and which appears to replicate real world cycling more closely.

VALUES OF AEROBIC CAPACITY IN HANDBALL AND VOLLEYBALL PLAYERS

Physical capacity of athletes is an important element of success in sports achievements. Aerobic capacity has been accepted as its major component. Maximal oxygen uptake (VO2max) has been regarded by majority of authors as the best indicator of aerobic capacity of an organism, and at the same time, the best indicator of an athlete's physical capacity. The aim of the investigation was to analyze the aerobic capacity as an indicator of physical capacity of athletes, differences in their aerobic capacity with regard to the kind of sport they are practicing, as well as the differences obtained when compared to physically inactive subjects. The investigation included the determination of absolute and relative VO2max in the total of 70 male examinees. The examinees were divided into two groups of active athletes (handball players (n=24) and volleyball players (n=20) of different profiles, while the third group of non-athletes served as control group. Maximal oxygen uptake was determined by performing the Astrand 6 minute cycle test. Peak values of VO2 max were recorded in the group of handball players (4,27±0,29 l/min), and they were statistically significantly higher (p<0,001) compared to other examined groups. In the group of volleyball players the oxygen uptake was 3,98±0,19 l/min, while statistically significantly lower values were reported in the group of non-athletes compared to the groups of athletes (p<0,01). A similar ratio of VO2 max values was also shown by the analysis of values expressed in relative units. Our results showed that peak values of VO2 max were obtained in handball players, and that handball as a sport requires higher degree of endurance compared to volleyball. Having considered the morphological and functional changes which are the consequence of the training process, it can be concluded that VO2 max values are statistically significantly higher in the groups of athletes compared to the group of non-athletes.

The association between ace gene variation and aerobic capacity in winter endurance disciplines.

The aim of the study was to examine the possible relationship between I/D polymorphism of ACE gene and selected indices of aerobic capacity among male and female athletes practising winter endurance sports. Sixty-six well-trained athletes (female n = 26, male n = 40), aged 18.4 ± 2.8 years, representing winter endurance sports (cross-country skiing, n = 48; biathlon, n = 8; Nordic combined, n = 10) participated in the study. Genotyping for ACE I/D polymorphism was performed using polymerase chain reaction. Maximal oxygen consumption (VO2max), maximal running velocity (Vmax) and running velocity at anaerobic threshold (VAT4) were determined in an incremental test to volitional exhaustion on a motorized treadmill. The ACE genotype had no significant effect on absolute VO2max, relative VO2max (divided by body mass or fat free body mass), VAT4 or Vmax. No interaction effect of gender x ACE genotype was found for each of the examined aerobic capacity indices. ACE gene variation was not found to be a determinant of aerobic capacity in either female or male Polish, well-trained endurance athletes participating in winter sports.

Performance enhancing genetic variants, oxygen uptake, heart rate, blood pressure and body mass index of elite high altitude mountaineers

To analyse and compare the ACE (angiotensin-converting enzyme), ACTN3 (actinin-3) and AMPD1 (adenosine monophosphate deaminase 1) genetic variants, oxygen uptake (VO2max), heart rate (HR), blood pressure (BP) and body mass index (BMI) of elite high altitude mountaineers and average athletes. Elite Bulgarian alpinists (n = 5) and control group of athletes (n = 72) were recruited. VO2max was measured using a treadmill graded protocol. HR, BP and BMI were recorded. Genotyping was done by polymerase chain reaction (PCR) amplification followed by agarose gel electrophoresis. Chi2-test and Fisher's exact test were used for statistical analysis. Alpinists showed significantly higher frequencies of 60% ACE I allele (p = 0.002), 50% ACTN3 X allele (p = 0.032) and 30% AMPD1 T allele (p = 0.003) compared to controls - 39%, 36%, 13%, respectively. ACE ID genotype prevalence and null DD genotype were observed in mountaineers. Higher absolute VO2max, but no differences in VO2max ml kg-1 min-1, HR, oxygen pulse, blood pressure and BMI were found. The ID genotype and higher frequencies of ACE I allele could contribute to successful high altitude ascents in mountaineers. The genetic make-up of the two mountaineers who made the summit of Mt Everest was distinctive, revealing ACE ID genotype, mutant ACTN3 XX and AMPD1 TT genotypes.

The Effect of Age-related Differences in Body Size and Composition on Cardiovascular Determinants of VO2max

A reduction in maximal stroke volume (SVmax) and total blood volume (TBV) has been hypothesized to contribute to the decline in maximal oxygen uptake (VO2max) with healthy aging. However, these variables have rarely been collected simultaneously in a board age range to support or refute this hypothesis. It is also unclear to what extent scaling size-related cardiovascular determinants of VO2max affects the interpretation of age-related differences. A retrospective analysis of VO2max, maximal cardiac output (QCmax), TBV, and body composition including fat-free mass (FFM) in 95 (51% M) healthy adults ranging from 19-86 years. Absolute and indexed VO2max, QCmax, and maximal heart rate decreased in both sexes with age (p ≤ .031). SVmax declined with age when scaled to total body mass or body surface area (p ≤ .047) but not when expressed in absolute levels (p = .120) or relative to FFM (p = .464). Absolute and indexed TBVs (mL/kg; mL/m(2)) were not significantly affected by age but increased with age in both sexes when scaled to FFM (p ≤ .013). A lower arteriovenous oxygen difference (a-vO2diff) contributed to the reduction in VO2max with age in treadmill exercisers (p = .004) but not in the entire cohort (p = .128). These results suggest (a) a reduction in absolute SVmax, and TBV do not contribute substantially to the age-related reduction in VO2max, which instead results from a smaller QCmax due to a lower maximal heart rate, and (b) body composition scaling methods should be used to accurately describe the effect of aging on physical function and cardiovascular variables.

Increased Hemoglobin Mass and VO2max With 10 h Nightly Simulated Altitude at 3000 m

To quantify the changes of hemoglobin mass (Hbmass) and maximum oxygen consumption (VO2max) after 22 days training at 1300-1800 m combined with nightly exposure to 3000-m simulated altitude. We hypothesized that with simulated 3000-m altitude, an adequate beneficial dose could be as little as 10 h/24 h. Fourteen male collegiate runners were equally divided into 2 groups: altitude (ALT) and control (CON). Both groups spent 22 days at 1300-1800 m. ALT spent 10 h/night for 21 nights in simulated altitude (3000 m), and CON stayed at 1300 m. VO2max and Hbmass were measured twice before and once after the intervention. Blood was collected for assessment of percent reticulocytes (%retics), serum erythropoietin (EPO), ferritin, and soluble transferrin receptor (sTfR) concentrations. Compared with CON there was an almost certain increase in absolute VO2max (8.6%, 90% confidence interval 4.8-12.6%) and a likely increase in absolute Hbmass (3.5%; 0.9-6.2%) at postintervention. The %retics were at least very likely higher in ALT than in CON throughout the 21 nights, and sTfR was also very likely higher in the ALT group until day 17. EPO of ALT was likely higher than that of CON on days 1 and 5 at altitude, whereas serum ferritin was likely lower in ALT than CON for most of the intervention. Together the combination of the natural and simulated altitude was a sufficient total dose of hypoxia to increase both Hbmass and VO2max.

Effect of exercise training intensity on adipose tissue hormone sensitive lipase gene expression in obese women under weight loss

BackgroundHormone sensitive lipase (HSL) is an enzyme that regulates adipose tissue lipolysis and plays an important role in chronic exercise-induced changes in adipose tissue metabolism. The purpose of this study was to determine whether aerobic exercise intensity influences abdominal adipose tissue HSL gene expression in obese women under weight loss. MethodsThirty women (body mass index (BMI) = 33.0 ± 0.7 kg/m2, age = 58 ± 1 years) completed one of three 20-week interventions: caloric restriction alone (CR only, n = 8), CR plus moderate-intensity exercise (CR + moderate-intensity, 45%–50% heart rate reserve (HRR), 3 day/week, n = 9), or CR plus vigorous-intensity exercise (CR + vigorous-intensity, 70%–75% HRR, 3 day/week, n = 13). Each group had a similar prescribed energy deficit comprised of underfeeding alone (2800 kcal/week for CR only) or underfeeding (2400 kcal/week) plus exercise (400 kcal/week). Body composition and maximal aerobic capacity (VO2max) were measured, and subcutaneous abdominal adipose tissue samples were collected before and after the interventions. Adipose tissue HSL gene expression was measured by real time reverse-transcriptase polymerase chain reaction. ResultsAll three interventions reduced body weight, fat mass, percent fat, and waist to a similar degree (all p < 0.01). In addition, all interventions did not change absolute VO2max, but increased relative VO2max (p < 0.05 to p < 0.01). Compared to pre-intervention, neither CR only nor CR + moderate-intensity changed adipose tissue HSL gene expression, but CR + vigorous-intensity significantly increased adipose tissue HSL gene expression (p < 0.01). The changes of HSL gene expression levels in the CR + vigorous-intensity group were significantly different from those in the CR only (p < 0.05) and CR + moderate-intensity (p < 0.01) groups. In the whole cohort, changes in adipose tissue HSL gene expression correlated positively to changes in absolute (r = 0.55, p < 0.01) and relative (r = 0.32, p = 0.09) VO2max. ConclusionThese results support a potential effect of aerobic exercise training intensity on hormone sensitive lipase pathway in adipose tissue metabolism in obese women under weight loss.

Predicting Maximal Aerobic Capacity ( JOURNAL/jscr/04.03/00124278-201203000-00019/OV0312_5/v/2021-02-09T093839Z/r/image-png O2max) from the Critical Velocity Test in Female Collegiate Rowers

The objective of this study was to examine the relationship between the critical velocity (CV) test and maximal oxygen consumption (VO2max) and develop a regression equation to predict VO2max based on the CV test in female collegiate rowers. Thirty-five female (mean ± SD; age, 19.38 ± 1.3 years; height, 170.27 ± 6.07 cm; body mass, 69.58 ± 0.3 1 kg) collegiate rowers performed 2 incremental VO2max tests to volitional exhaustion on a Concept II Model D rowing ergometer to determine VO2max. After a 72-hour rest period, each rower completed 4 time trials at varying distances for the determination of CV and anaerobic rowing capacity (ARC). A positive correlation was observed between CV and absolute VO2max (r = 0.775, p < 0.001) and ARC and absolute VO2max (r = 0.414, p = 0.040). Based on the significant correlation analysis, a linear regression equation was developed to predict the absolute VO2max from CV and ARC (absolute VO2max = 1.579[CV] + 0.008[ARC] - 3.838; standard error of the estimate [SEE] = 0.192 L·min(-1)). Cross validation analyses were performed using an independent sample of 10 rowers. There was no significant difference between the mean predicted VO2max (3.02 L·min(-1)) and the observed VO2max (3.10 L·min(-1)). The constant error, SEE and validity coefficient (r) were 0.076 L·min(-1), 0.144 L·min(-1), and 0.72, respectively. The total error value was 0.155 L·min(-1). The positive relationship between CV, ARC, and VO2max suggests that the CV test may be a practical alternative to measuring the maximal oxygen uptake in the absence of a metabolic cart. Additional studies are needed to validate the regression equation using a larger sample size and different populations (junior- and senior-level female rowers) and to determine the accuracy of the equation in tracking changes after a training intervention.

Pilot Study of an Active Screen Time Game Correlates with Improved Physical Fitness in Minority Elementary School Youth.

The aim of our feasibility study was to examine the acceptability and utility of "Dance Dance Revolution" (DDR) (Konami of America, Redwood City, CA)) to increase physical fitness in 8-11-year-old black and Hispanic youth. Twenty-eight 4(th) and 5(th) grade children attending an afterschool program participated. Outcomes included physical activity, physical fitness, use of home DDR, survey of safety and acceptability, anthropometrics, and fasting metabolic profile measured at baseline, 12 weeks, and 30 weeks. At 12 weeks, physical fitness (maximum O2 uptake [VO2max]) increased by 4.9±9.9 percent and was sustained through 30 weeks, when the VO2max was 105.0±9.9 percent (range, 93.0-133.9 percent) of baseline values. Absolute VO2max increased by 2.97±4.99 mL/kg/minute (95% confidence interval 0.75-5.19, P=0.013). Participants maintained an average of 1.12 hours/day of increased movement to music. Trends suggested increased total moderate-vigorous physical activity, decreased light activity, and a modest increase in sedentary screen time. There were no significant changes in body mass index, fasting lipids, or glucose. Participants and parents approved of the activity. DDR appears feasible and acceptable to minority youth. DDR may increase moderate-vigorous physical activity and improve physical fitness in at-risk populations.

Allometric scaling of peak power output accurately predicts time trial performance and maximal oxygen consumption in trained cyclists

ObjectiveThe purpose of this study was to determine if peak power output (PPO) adjusted for body mass0.32 is able to accurately predict 40-km time trial (40-km TT) performance.Methods45 trained male...

Relationship Of Bone Mineral Density, Aerobic Power, Muscular Strength, And Body Composition In Adult Males

Indirect indicators of bone mineral density (BMD) can offer important and useful information to practitioners. Finding a more time and cost effective method for estimating BMD in different locations could aid in the treatment and prevention of osteoporosis and osteopenia. Increased muscle strength has been shown to correlate with increased total body BMD in both men and women. There have been a number of studies examining predictors of BMD in women; however there have been substantially fewer studies involving men. This over-representation of the female population has led to the belief that osteoporotic fractures are less frequent in men where in actuality the rate of hip fractures increases more dramatically in men with age. PURPOSE: The purpose of this study was to examine the relationship between muscular strength, aerobic capacity, body composition and BMD in healthy male subjects. METHODS: Participants were seven physically active, adult men (mean age: 28.3 years; range: 21-38). Maximal oxygen consumption (VO2max) was directly measured during treadmill running. Bone mineral density and body composition were determined using Dual X-Ray Absorptiometry (DEXA). Upper body strength was measured with a hand grip dynamometer, and lower body strength (isometric leg extension) using a cable tensiometer. Pearson Correlation coefficients were used to test for significant relationships between the measured variables. RESULTS: Lower body strength increased concomitant with lower body (r = 0.676), total body (r = 0.709), and total spine BMD (r = 0.915); this was also seen in the thoracic (r = 0.931) and lumbar spine (r = 0.891). As lean body mass (LBM) increased, mean upper body BMD increased (r = 0.646). As total body % fat increased, upper body strength increased (r = 0.825). There were no significant correlations between BMD and absolute or relative VO2max. There were also no significant correlations between lower body strength and VO2max. CONCLUSION: In physically active, adult men, lower body strength is a strong predictor of increased total spine BMD, particularly in the thoracic and lumbar regions. LBM is a strong indicator of upper body BMD. Total body % fat is also a strong predictor of increased upper body strength. Neither absolute nor relative VO2max were good indicators of BMD or lower body strength.

FIT Kids: Time in target heart zone and cognitive performance

Objective This present study examined time spent in the target heart zone (THZ) and its relationship to tasks requiring variable amounts of executive control function in prepubescent children participating in a 9-month randomized controlled physical activity program. Methods A sample of 59 participants performed the Stroop Color-Word Test and the Comprehensive Trail Making Test cognitive assessments. Heart rate data were collected during participation in the physical activity program using E600 heart rate monitors (Polar, Finland). Results There was a significant difference, F(1, 58)=7.44, p <.009, between males and females for relative VO2max, but not absolute (p=.69) or percent VO2max (p=.73). Regression analysis identified KBIT, age, and mean time above the THZ as significant predictors of performance in the Stroop Color-Word condition, F(1, 56)=5.21, p=.02. KBIT and mean time above the THZ were significant predictors for Trails B, F(1, 56)=7.60. Conclusions These results suggest that heart rate, as a measure of physical activity intensity, should be closely monitored during research that is intended to make inferences about its effects on cognitive performance as participation in vigorous activities may have specific benefits over lower intensities among prepubescent children.