Higher VO2max Research Articles

PP.38.05] THE ASSOCIATION OF BLOOD PRESSURE AND BODY COMPOSITION MEASURES WITH MAXIMAL AEROBIC CAPACITY IN A SWISS WORKING POPULATION

Objective: This study aimed to examine the association of maximal aerobic capacity (VO2max) with blood pressure (BP), heart rate (HR), body mass index (BMI) and waist circumference (WC) in a representative sample of healthy Swiss employees. Design and method: In this cross-sectional study, 337 healthy and at least 80% employed adult workers were recruited in the Basel region, Switzerland. Gender, age and smoking status (yes, no more, never) were recorded. Height, weight and WC were measured and BMI was calculated. VO2max was determined using the multistage 20-meter shuttle run test. Subjects were categorized according to the 25th (P25) and 75th percentile (P75) of VO2max. HR, systolic and diastolic BP were assessed at rest prior to testing and at test termination (maximal HR) respectively two minutes after the end of the test. Group differences between P25 and P75 were analysed with Student-t test or Mann-Whitney test. Forced-entry multiple linear regression analysis was performed to identify predictors of VO2max. Results: Complete data were available from 303 subjects aged 18 to 61 years. Descriptive statistics for total subjects, P25 and P75 are presented in Table 1. Compared to P25, subjects in P75 were mostly male, younger, had lower BMI and WC, higher resting and recovery systolic BP, lower resting but higher maximal HR and a greater difference between maximal and resting as well as recovery HR. Multiple linear regressions (Table 2) revealed that a higher VO2max was associated with a greater difference between maximal and resting HR, whereas female gender, increasing age, higher WC and current smoking contributed to a decrease of VO2max. BMI, ex-smoking, differences in BP and maximal-to-recovery HR were not related to VO2max.Conclusions: This study provides evidence that diastolic BP is not affected by aerobic exercise, while systolic BP was increased in the fittest category. The present findings suggest that maximal aerobic capacity is associated with maximal and resting HR, but not with recovery HR. WC, but not BMI, should be preferably used to assess the association between aerobic capacity and body composition.

Physical Workload and Work Capacity across Occupational Groups.

This study aimed to determine physical performance criteria of different occupational groups by investigating physical activity and energy expenditure in healthy Swiss employees in real-life workplaces on workdays and non-working days in relation to their aerobic capacity (VO2max). In this cross-sectional study, 337 healthy and full-time employed adults were recruited. Participants were classified (nine categories) according to the International Standard Classification of Occupations 1988 and merged into three groups with low-, moderate- and high-intensity occupational activity. Daily steps, energy expenditure, metabolic equivalents and activity at different intensities were measured using the SenseWear Mini armband on seven consecutive days (23 hours/day). VO2max was determined by the 20-meter shuttle run test. Data of 303 subjects were considered for analysis (63% male, mean age: 33 yrs, SD 12), 101 from the low-, 102 from the moderate- and 100 from the high-intensity group. At work, the high-intensity group showed higher energy expenditure, metabolic equivalents, steps and activity at all intensities than the other groups (p<0.001). There were no significant differences in physical activity between the occupational groups on non-working days. VO2max did not differ across groups when stratified for gender. The upper workload limit was 21%, 29% and 44% of VO2max in the low-, moderate- and high-intensity group, respectively. Men had a lower limit than women due to their higher VO2max (26% vs. 37%), when all groups were combined. While this study did confirm that the average workload limit is one third of VO2max, it showed that the average is misrepresenting the actual physical work demands of specific occupational groups, and that it does not account for gender-related differences in relative workload. Therefore, clinical practice needs to consider these differences with regard to a safe return to work, particularly for the high-intensity group.

A Comparison Of Oxidative Stress Markers In Active Vs. Sedentary College Age Students

PURPOSE: To determine the effects of activity level, aerobic capacity and body mass index (BMI) on markers of oxidative stress in college age females. METHODS: 17 female collegiate cross-country athletes (19.1 ± 0.86 years old) and 17 female sedentary college students (21.5 ± 1.8 years old) were examined. Measures of oxidative stress (d-ROMs) and antioxidant capacity (PAT) were obtained using the FRAS-4 Evolvo Analytical System. Height, weight and BMI were recorded for each subject. For the sedentary group, a subjects’ maximum aerobic capacity (VO2 max) was estimated via a submaximal 1-mile walk/jog test. For the cross-country athletes, VO2 max was directly measured using a Parvo Medics TrueOne metabolic cart during an incremental treadmill test to volitional exhaustion. A t-test was used to compare differences between groups. A Pearson correlation was used to determine if a linear relationship existed between any of the test variables. RESULTS: Sedentary subjects demonstrated significantly (p<0.01) higher d-ROMs values (547 ± 172) compared to athletes (385 ± 156). There was no difference in PAT values between the two groups (Sedentary 2287 ± 329, Athletes 2295 ± 518.) Cross-Country athletes had a significantly lower body mass index (20.68 ± 1.64, 26.11 ± 5.11) and a higher VO2 max (50.6 ± 4.70, 36.45 ± 3.29) compared to the sedentary group. There was a strong positive correlation between BMI and d-ROMs (r=0.53, p<0.001) and a strong negative correlation between d-ROMs and VO2max (r=-0.56, p<0.001). CONCLUSION: Elevated BMI, reduced aerobic capacity and a sedentary lifestyle may be associated with increased oxidative stress in college age individuals. Given the established association between oxidative stress and medical conditions such as cardiovascular disease, diabetes and certain types of cancer, this may place these individuals at a greater risk for medical co-morbidities. Supported by Quinnipiac University, School of Health Sciences

Search for associations between G/A polymorphism of the EPAS1 gene and the maximal oxygen consumption in Russian athletes

This study investigates associations between G/A polymorphism of the epithelial PAS domain protein 1 (EPAS1) gene (rs1867785) and the maximum rate of oxygen consumption (VO2max) in male Russian athletes. The study engaged 241 male athletes from different sports; the control group of nonathletes included 92 subjects. Increased frequencies of the AA and AG genotypes of the EPAS1 gene (χ2 = 14.16, p = 0.03) were found in the cohort of male athletes. The frequencies of these alleles in the subgroups with moderate (EPAS1*A 38.1% and EPAS1*G 61.9%) and high (EPAS1*A 41.8% and EPAS1*G 58.2%) VO2max values significantly differed from those in the control group (χ2 = 7.53, p = 0.006 and χ2 = 6.58, p = 0.01, respectively). The higher aerobic capacities are probably associated with the presence of at least one minor A allele of the EPAS1 gene in the genome.

Maximum oxygen uptake and cardiovascular response of Professional male football and Basketball players to Chester step test.

The cardiovascular response to exercise has several variables but this study will be limited to the heart rate response, blood pressure response and predicted VO2 max. These variables are what this study will be utilizing to evaluate the fitness level of the participants. The purpose of this study was to estimate the maximum oxygen uptake (VO2 max) and compare the cardiovascular response of professional male football players and basketball players to Chester step bench test.A total of 100 athletes (50 football players and 50 basketball players) recruited through convenience sampling participated in the study. The research design was quasi experimental research design. The instruments used were heart rate monitor, electronic blood pressure monitor, 30cm Chester step, stop watch, mobile metronome version 1.2.4, height meter, bathroom scale. The V02max was estimated from HR recovery (HRrec) after 15seconds using the equation V02max=111.3-(0.42 xHRrec).Comparative analysis of the data was done using descriptive statistics of mean and standard deviation, and inferential statistics of independent t-test with alpha level of significance of 0.05. In the result, Significant differences were recorded between the VO2 max of football players 81.15kg/ml/min and basketball players 72.39kg/ml/min; heart rate 72.10bpm and 93.58bpm; systolic blood pressure 147.90mmHg and 142.46mmHg; while there was no statistically significant difference in their diastolic blood pressure 81.820mmHg and 81.020mmHg. The study showed that football players had significantly higher VO2 max (81.14±0.66 ml/kg/min), than the basketball players (72.38±0.78 ml/kg/min), indicating that football players had more aerobic capacity than basketball players. High VO2 max is the primary indicator of aerobic fitness, cardiovascular health, and endurance performance. Coaches of different football clubs and basketball clubs should take serious the matter of consistent training of their players to improve and avoid decline in their cardiorespiratory fitness. Individuals should cultivate the habit of exercising in order to improve their cardiorespiratory fitness and minimize the risk of some diseases associated with low cardiorespiratory fitness.

Cardiorespiratory fitness in outpatients with bipolar disorder versus matched controls: An exploratory study

BackgroundPatients with bipolar disorder (BD) are approximately twice as likely to die prematurely due cardiovascular diseases (CVD) than the general population. Cardiorespiratory fitness (CRF) is an important health outcome measure, predictive for CVD and premature mortality. AimsThe aim of the current study was to compare the CRF of outpatients with BD versus age-, gender-, and body mass index (BMI)-matched healthy controls (HC). A secondary aim was to assess potential correlates of CRF. MethodsAll participants underwent a maximal incremental exercise test to measure the maximum oxygen uptake (VO2max, the golden standard assessment of cardiorespiratory fitness), wore a Body Sensewear Armband for 5 subsequent days to assess their physical activity behavior and completed the Positive-and-Negative-Affect-Schedule (PANAS). ResultsOutpatients with BD (n=20; 47.8±7.6years) had a significantly lower VO2max compared with HC (n=20; 47.8±7.6years) (26.0±7.3 versus 30.4±6.5ml/min/kg, P=0.047). A higher VO2max was correlated with younger age, higher active energy expenditure, higher PANAS positive and lower PANAS negative affect scores and a lower antipsychotic medication dose. LimitationsThe limited sample and cross-sectional design preclude definitive conclusions. ConclusionsCompared with HC, outpatients with BD have reduced CRF levels of approximately 4.4ml/min/kg. In the general population such reductions are associated with a 20% increased premature mortality risk. Interventions targeting CRF in BD are required. Although more research is needed, clinicians should consider the utility of objective assessments of CRF for risk stratification in outpatient settings.

Cardiorespiratory Responses of Professional Male Volleyball and Basketball Players to Harvard Step Test

Maximal rate of oxygen uptake is one of the most commonly measured parameters in basic and physiological sciences and it is frequently used to indicate the cardio-respiratory fitness of an individual. The purpose of this study was to compare the maximal oxygen uptake (VO2max) and the cardio-respiratory responses of professional volleyball and basketball players to Harvard step test.Twenty-five volleyball players of mean age, height and weight of 26.16yrs, 1.80m, and 80.20kg and twenty-five basketball players of mean age, height and weight as 25.32yrs, 1.88m, 86.48kg were selected through purposive sampling and they performed the exercise protocol for five minutes after which there blood pressure and heart rate (HR) responses were measured. Mean arterial pressure (MAP) and rate pressure product (RPP) was also estimated from the blood pressure responses. The VO2max (maximal oxygen uptake) was estimated using the equation; Fitness index (Short form) = (100 x test duration in seconds) divided by (5.5 x pulse count between 1 and 1.5), RPP was computed using the equation; HR x systolic blood pressure (SYS) and the MAP was calculated using; MAP = Pdiast+ 1/3(Psyst- Pdiast). Comparative analysis was done using descriptive statistics of mean and standard deviation, inferential statistics of independent t-test and Pearson moment product correlation with alpha level of significance set at 0.05.Statistically significant differences were recorded between VO2 max of volleyball players; 39.07ml/kg/min, and basketball players 25.46ml/kg/min, while no statistically significant differences were recorded in their HR; 103.5bpm and 105.3bpm, SYS; 145.4mmHg and 136.7mmHg, diastolic blood pressure(DBP); 76.3mmHg and 74.7mmHg, RPP; 15200mmHg.bpm and 14548mmHg.bpm, MAP; 91.5mmHg and 89mmHg of professional basketball and volleyball players respectively. Positive significant correlations were recorded between the VO2max and RPP (p=0.001), MAP and RPP (p=0.02), MAP and SYS (p=0.00) of basketball players. A Positive significant correlation was recorded between the MAP and RPP (p=0.001), MAP and SYS (p=0.00) of volleyball players. A negative significant correlation was recorded between the VO2max and RPP (p= -0.8) of volleyball players. These data shows that volleyball players had higher VO2max than basketball players which implies that they have better cardio-respiratory endurance level. Frequent training among these athletes will help to reduce the incidence of detraining as this will invariably lead to decrease in aerobic capacity and cardio-respiratory fitness.

Outcome after video-assisted thoracoscopic surgery and open pulmonary lobectomy in patients with low VO2 max: a case-matched analysis from the ESTS database†.

The aim was to verify the association of low VO2 max with postoperative morbidity and mortality after video-assisted thoracoscopic surgery (VATS) or open pulmonary lobectomy using the European Society of Thoracic Surgeons (ESTS) database. A retrospective analysis of data collected from the ESTS database was conducted. A total of 1684 lobectomy patients with available VO2 max values were included (2007-14). Patients operated through VATS (281 patients) or thoracotomy (1403 patients) were separately analysed. Propensity score analyses were performed to match patients with high (≥15 ml/kg/min) and low VO2 max (<15 ml/kg/min) for each approach. The following variables were used to construct the score: age, body mass index, predicted postoperative forced expiratory volume in 1 s (%), coronary artery disease, American Society of Anaesthesiology grade and Eastern Cooperative Oncology Group performance score. Cardiopulmonary morbidity and 30-day mortality were compared between the matched groups. Mean VO2 max was 17.4 ml/kg/min. A total of 471 patients (28%) had low VO2 max. Overall postoperative cardiopulmonary morbidity and mortality rates were 30% (505 patients) and 4.1% (70 patients), respectively. Morbidity and mortality rates in low VO2 max patients were 33% (156 patients) and 6% (28 patients), respectively. After VATS, cardiopulmonary morbidity and mortality rates were 2-fold (13 of 72, 18% vs 143 of 399, 36%, P = 0.003) and 5-fold (1 of 72, 1.4% vs 27 of 399, 6.7%, P = 0.09) lower compared with thoracotomy. Matched comparison after thoracotomy (399 pairs): Mortality was significantly higher in patients with low VO2 max (27 patients, 6.7%) compared with those with high VO2 max (11 patients, 2.8%, P = 0.008). Complication rates were similar between the two groups (low VO2 max: 143 patients, 36% vs high VO2 max: 133 patients, 33%, respectively, P = 0.5). Matched comparison after vats (72 pairs): Morbidity and mortality rates of patients with low VO2 max were similar to those of patients with high VO2 max (morbidity: 13 patients, 18% vs 17 patients, 24%, P = 0.4; mortality: 1 patient, 1.4% vs 4 patients, 5.5%, P = 0.4). Low VO2 max was not associated with an increased surgical risk after VAT lobectomy, which challenges the traditional operability criteria when this technique is used.

Physiological, physical and on-ice performance criteria for selection of elite ice hockey teams.

The purpose of this study was to examine physiological and physical determinants of ice-hockey performance in order to assess their impact on the result during a selection for ice hockey. A total of 42 ice hockey players took part in the selection camp. At the end of the camp 20 best players were selected by team of expert coaches to the ice hockey team and created group G1, while the second group (G2) consisted of not selected players (non-successful group Evaluation of goodness of fit of the model to the data was based on the Hosmer Lemeshow test. Ice hockey players selected to the team were taller 181.95±4.02 cm, had lower% body fat 13.17±3.17%, a shorter time to peak power 2.47±0.35 s, higher relative peak power 21.34±2.41 W·kg−1 and higher relative total work 305.18±28.41 J·kg−1. The results of the aerobic capacity test showed significant differences only in case of two variables. Ice hockey players in the G1 had higher VO2max 4.07±0.31 l·min−1 values than players in the G2 as well as ice hockey players in G1 showed a higher level of relative VO2max 51.75±2.99 ml·min−1·kg−1 than athletes in G2. Ice hockey players selected to the team (G1) performed better in the 30 m Forwards Sprint 4.28±0.31 s; 6x9 Turns 12.19±0.75 s; 6x9 stops 12.79±0.49 s and Endurance test (6x30 m stops) 32.01±0.80 s than players in G2. The logistic regression model showed that the best predictors of success in the recruitment process of top level ice hockey players were time to peak power, relative peak power, VO2max and 30 m sprint forwards on ice. On the basis of the constructed predictive logistic regression model it will be possible to determine the probability of success of the athletes during following the selection processes to the team.

White matter microstructure mediates the relationship between cardiorespiratory fitness and spatial working memory in older adults

White matter structure declines with advancing age and has been associated with a decline in memory and executive processes in older adulthood. Yet, recent research suggests that higher physical activity and fitness levels may be associated with less white matter degeneration in late life, although the tract-specificity of this relationship is not well understood. In addition, these prior studies infrequently associate measures of white matter microstructure to cognitive outcomes, so the behavioral importance of higher levels of white matter microstructural organization with greater fitness levels remains a matter of speculation. Here we tested whether cardiorespiratory fitness (VO2max) levels were associated with white matter microstructure and whether this relationship constituted an indirect pathway between cardiorespiratory fitness and spatial working memory in two large, cognitively and neurologically healthy older adult samples. Diffusion tensor imaging was used to determine white matter microstructure in two separate groups: Experiment 1, N=113 (mean age=66.61) and Experiment 2, N=154 (mean age=65.66). Using a voxel-based regression approach, we found that higher VO2max was associated with higher fractional anisotropy (FA), a measure of white matter microstructure, in a diverse network of white matter tracts, including the anterior corona radiata, anterior internal capsule, fornix, cingulum, and corpus callosum (PFDR-corrected<.05). This effect was consistent across both samples even after controlling for age, gender, and education. Further, a statistical mediation analysis revealed that white matter microstructure within these regions, among others, constituted a significant indirect path between VO2max and spatial working memory performance. These results suggest that greater aerobic fitness levels are associated with higher levels of white matter microstructural organization, which may, in turn, preserve spatial memory performance in older adulthood.

Assessment of functional, coordination and power fitness of 7-8 form boys

Purpose : The purpose of this study was to compare some anthropometric, body composition indexes and VO2max of Ahvaz elite soccer players of different playing positions. Material : Participants were 60 male soccer players (age 24.31±4.20 years) from 4 teams in the two highest divisions in Iran. The sample included 8 goalkeepers, 18 defenders, 20 midfielders and 14 strikers. Anthropometric variables of subjects (height, weight and BMI) and body composition (%BF) were measured. Skinfold thickness measurements were taken using Harpenden skinfold calipers at three sites (triceps, subscapular and abdominal) and the VO2max of the subjects was estimated by participation in a multi-stage 20m shuttle-run test. One-way ANOVA and Tukey testes were used for possible differences in test variables between different player positions. Results : Results revealed that the goalkeepers were significantly (p-0.05) the tallest, heaviest and had lower VO2max than another positions. Beside the midfielders had significantly (p-0.05) higher VO2max than the goalkeepers. Also, no difference in estimated body fat percentage and BMI was observed between players of all positions. Discussion: Thus, it can be concluded that anthropometric and physiological differences are exist among soccer players who play in different positions. These differences fit with their different workload in a game. Therefore, programs must be include specific sessions for each positional role.

Is Cardiopulmonary Fitness Level a Risk Factor in Young Saudi Females?

Low physical fitness is one of the all-cause mortality risk factors. This study aims to estimate cardiopulmonary fitness (VO2 max) in young Saudi females and correlate it to anthropometric and hemodynamic parameters. Forty-eight young Saudi females completed an exercise stress test until exhaustion. Basal and maximum pulse rate, arterial blood pressure, VO2max and other anthropometric data were measured. The population was divided into low and high VO2 max groups and a comparison was run using student t-test. Correlation was tested between VO2 max and other measured parameters. The mean VO2 max of the sample population was low (33.6 ± 8.2 mL/ (kg min) with 37.5% exhibiting fair to very poor VO2 max value. The low VO2 max group was characterized by higher body mass index, exercise diastolic and mean arterial blood pressure when compared to normal VO2 max group, indicating a strong negative correlation. This study revealed a low cardiopulmonary fitness in young Saudi females and showed a strong association between VO2 max and increased body fat and maximum exercise diastolic blood pressure. These findings provide reliable indicators of increased all-cause mortality risk in young Saudi females and increase the urgency of prompt action.&#x0D;

The Influence Of Ribose Ingestion On Recovery And Performance In Healthy Individuals.

PURPOSE: Skeletal muscle adenosine triphosphate (ATP) levels are depleted during and following high intensity exercise. Previous studies have shown that recovery of these lower ATP levels can take days, which ultimately can affect performance. Ribose has been shown to enhance the recovery in ATP; however, how is performance affected with this metabolic recovery? Therefore, we investigated the influence of ingesting 10 g/day of D-ribose (DR) on muscular recovery, performance, and metabolism during and following a multi-day exercise regimen. METHODS: A double blind, crossover study in 18 healthy subjects compared 10 g/day of DR to 10 g/day of dextrose (DEX, control). All subjects completed 2 days of loading with either DR or DEX, followed by 3 days of additional supplemental treatment, as well as undergoing high intensity interval exercise. Exercise assessment protocol consisted of cycling for 60 min (8 min of exercise at 60% and 2 min at 80% VO2max), followed by a 2 min power test evaluation (PO). RESULTS: Mean and peak PO increased from day 1 to day 3 by 2% (p = 0.04) and 6% (p = 0.03), respectively, for DR, but was only maintained with DEX. Rating of Perceived Exertion (RPE) was significantly lower for DR than DEX. Subjects were then further assessed between the low and high VO2max values. The lower VO2max subjects had a significant increase in CK (by 57%), as well as a 4% greater increase in HR, and greater RPE with DEX as compared to DR. Further, in the lower VO2max DR subjects, there was a significantly lower exercising HR and RPE (13.1 +/- 1.7 vs. 13.7 +/- 1.5), and an improvement in PO. No differences in HR, CK, BUN, GLUC, or lactate were found between either supplement. However, there was a 40% increase in the main effect of time for CK elevation regardless of treatment. CONCLUSIONS: DR supplementation led to greater performance changes than DEX during and following high intensity interval cycling exercise. Furthermore, upon sub group analysis between VO2max differences revealed additional benefits with DR. DR supplementation within this lower VO2max group resulted in maintenance in exercise performance, as well as potentially lessening muscular cell damage which can greatly influence cellular recovery and subsequent performance.

The Godin-Shephard leisure-time physical activity questionnaire: validity evidence supporting its use for classifying healthy adults into active and insufficiently active categories.

This study provided validity evidence for the Godin-Shephard Leisure-Time Physical Activity Questionnaire (GSLTPAQ) to classify respondents into active and insufficiently active categories. Members of a fitness center [45 women and 55 men; mean (SD) age=45.5 (10.6) yr.] completed the questionnaire. Using only moderate and strenuous scores, those with a leisure score index≥24 were classified as active; those with a score≤23 were classified as insufficiently active. VO2max, percentage of body fat, and electronic records of fitness center attendance were the validation variables. In a visit to the fitness center, participants completed the GSLTPAQ and a certified exercise specialist performed a physical fitness evaluation. A multivariate analysis of covariance (MANCOVA) indicated the group of respondents classified as active had higher VO2max and lower percentage of body fat than the group of respondents classified as insufficiently active. An analysis of covariance (ANCOVA) indicated the group of respondents classified as active had higher electronic records of fitness center attendance than the group of respondents classified as insufficiently active. Therefore, these pieces of validity evidence support the use of the questionnaire's classification system among healthy adults.

Cardiorespiratory fitness in groups with different physical activity levels.

The aim of the study was to determine how different categorizations of self-reported and objectively measured physical activity (PA) reflect variations in cardiorespiratory fitness (VO2max ). A total of 759 individuals (366 women) with a mean age of 48.5 years (SD 14.4) wore an accelerometer (ActiGraph GT1M) for seven consecutive days and answered the short International Physical Activity Questionnaire (IPAQ). VO2max was directly measured during a continuous graded exercise treadmill test until exhaustion. Men and women categorized as highly active by IPAQ had 9% and 13% higher VO2max , respectively, than those reporting a low PA level (P < 0.05). Men and women meeting the PA recommendation of 150 min/week of daily moderate intensity PA, measured by accelerometer, had 13% and 9% higher VO2max , respectively, than participants not meeting this recommendation (P < 0.01). No significant differences in average sedentary time, analyzed in total min/day and in bouts of 10 and 30 min, were found between participants with high or low cardiorespiratory fitness. However, women spent less time than men in bouts of sedentary behaviors. Self-reported PA by IPAQ and objectively measured PA by accelerometer were both useful instruments for detecting differences in VO2max .

Influence of cardiorespiratory fitness on PPARG mRNA expression using monozygotic twin case control.

The influence of cardiorespiratory fitness (VO2max) on anthropometric variables and PPARG mRNA expression was investigated. Monozygotic twin pairs aged 11–18 years were grouped into discordant (D) and concordant (C) high and low VO2max groups. VO2max was determined by progressive maximal exercise test on treadmill with gas exchange analysis. Body mass (BM), BMI, waist circumference (WC), triceps (TR), and subscapular (SB) skinfold thicknesses were measured. Twins from the discordant group had differences in VO2max values (D-high = 45.9 ± 10.0 versus D-low = 32.4 ± 10.6 mL·kg−1·min−1, P = 0.025), while no differences were found in the concordant group (C-high = 42.4 ± 9.2 versus C-low = 38.8 ± 9.8 mL·kg−1·min−1, P = 0.952). In discordant group, VO2max was negatively correlated with TR + SB (r = −0.540, P = 0.021) and positively correlated with PPARG expression in leukocytes (r = 0.952, P = 0.001). Moreover, PPARG expression was directly correlated with BM (r = 0.714, P = 0.047) and height (r = 0.762, P = 0.028). In concordant twins, VO2max was inversely correlated with BM (r = −0.290, P = 0.027), BMI (r = −0.472, P = 0.001), WC (r = −0.426, P = 0.001), and TR + SB (r = −0.739, P = 0.001). Twins D-high had 1.78-fold greater PPARG expression when compared with twins D-low (P = 0.048). In conclusion, the cardiorespiratory fitness may modulate PPARG expression in childhood and adolescence, independently of the genetic background.

Relationship between blood pressure and physical performance

Background: Changes in blood pressure during subjects’ exercise are individually different. The reasons of these differences are unknown. Aim of the study: The aim of this paper is to investigate the rate of changes in cardiovascular system at rest and at physical load which enhance systolic blood pressure (SBP) = 200 mmHg in people with different physical performance. Material and methods: The studies included 18 soccer players and 14 students who do not practice any sport, whose age, body mass, body height and BMI have been similar, and who at baseline were measured systolic blood pressure (SBPr), diastolic blood pressure (DBPr) and heart rate (HRr). Then, the subjects performed exercise on a cycloergometer with increasing intensity in which at the level of the systolic blood pressure = 200 mm Hg (SBP200) were measured DBP200 and HR200. In terms of resting and exercise time the size of the mean arterial pressure (MAPr, MAP200), pulse pressure (PPr, PP200) and rate-pressure product (DPr, DP200) were calculated. Moreover the power achieved in PWC170 test (W and W/kg) and maximal oxygen uptake (VO2max) (ml/min and ml/min/kg) were also calculated. Results: Soccer players have reached a higher power in PWC170 and higher VO2max and lower HR200 and DP200 (p&lt;0,001), as well as lower values of HRr (p&lt;0,01) than students however SBP, DBP, MAP and PP registered during rest and during exercise did not differ between the groups. Among the players power reached at PWC170 (W) correlate negatively with DP200 – (p&lt;0,05) and VO2max (ml/min; ml/min/kg) also correlated negatively with HRr (p&lt;0,05, p&lt;0,01). Among students power reached at PWC170 (W, W/kg) and VO2max (ml/min, ml/min/kg) correlate negatively with HR200 and DP200. Moreover VO2max (ml/min/kg) correlate negatively with HRr. Conclusions: Studies have shown that, despite differences in physical performance of both groups, there were no significant changes in blood pressure at rest or modified during exercise. However, at extremely high increase in SBP improved economization in function of the heart and circulatory system independent of the size of physical performance of the subjects were observed.

Clinical characteristics of OGTT-derived hepatic- and muscle insulin resistance in healthy young men.

[Purpose]Insulin inhibits glucose release in the liver but increases glucose absorption in muscles. When insulin cannot properly control glucose, it negatively affects glucose metabolism and, furthermore, contributes to the onset of metabolic syndrome and chronic disease. Therefore, this study's goal is to understand the clinical characteristics of hepatic insulin resistance and muscle insulin sensitivity in healthy young men.[Methods]Twenty-eight healthy young men (age 23.3 ± 0.5; mean ± SE) participated in this study. Liver function and blood lipids were measured by blood sampling from brachial vein after participants fasted the previous day. Hepatic insulin resistance and muscle insulin sensitivity were evaluated using two-hour OGTT along with surrogate index related to insulin sensitivity. The VO2max was evaluated using cycle ergometer. Systemic insulin sensitivity was evaluated using two-hour euglycemic hyperinsulinemic clamp method.[Results]Hepatic insulin resistance showed a significant correlation with body fat (r = 0.609, p < 0.05). Also, hepatic insulin resistance showed a significant correlation with GOT (r = 0.467), GPT (r = 0.434), and γ-GTP (r = 0.375), reflecting liver functions, as well as showing a significant correlation with hs-CRP (r = 0.492, p < 0.05). On the other hand, muscle insulin sensitivity had no correlation with neither body fat nor liver function index (p > 0.05), and among surrogate indexes, it showed a significant correlation with Avignon (r = -0.493) and Matsuda index (r = -0.577). Glucose infusion rate, using the clamp method, showed a significant correlation with muscle insulin sensitivity (r = 0.448, p < 0.05). The VO2max had a significant correlation with hepatic insulin resistance (r = -0.435, p < 0.05) and muscle insulin sensitivity (r = 0.474, p < 0.05), respectively.[Conclusion]For young men in their 20's, the OGTT-based hepatic insulin sensitivity was an indicator of hepatic function and body fat but muscle insulin sensitivity was related to peripheral insulin sensitivity. Also, for young men, higher VO2max indicated lower hepatic insulin resistance and higher muscle insulin sensitivity.

Physiological and performance characteristics of road, mountain bike and BMX cyclists

The purpose of this research was to quantify several physiological and power output characteristics of high-performance road, cross-country mountain bike (XCMB), downhill mountain bike (DHMB) and bicycle motocross (BMX) cyclists. Twenty-four high-performance cyclists (27 ± 7 yr; 182 ± 6 cm; 79.3 ± 9.7 kg; ∑7SF 69 ± 27 mm; 61.4 ± 9.9 mL·kg -1 ·min -1 ) completed both an incremental ramp test and a power profile assessment (PPA) across two separate testing sessions. The PPA consisted of maximal efforts lasting 5 s, 15 s, 30 s, 60 s, 240 s, and 600 s. The ramp test provided measures of VO 2MAX , maximal aerobic power (MAP) and individual VO 2 -power regression equations, whilst the PPA determined metabolic costs, anaerobic capacity and power output across each effort. The data demonstrated that road and XCMB cyclists possessed significantly (p<0.05) higher VO 2MAX (65.3-69.6 vs. 52.4-55.3 mL . kg -1. min -1 ) and anaerobic capacities (1.7-1.8 vs. 0.9-1.3 L) than the DHMB and BMX cyclists. Further, the same cohorts produced significantly (p ≤ 0.05) greater MAP (5.8-6.3 vs 4.4-4.7 W . kg -1 ), as well as relative mean power output across efforts lasting ≥15 s. The BMX and DHMB cyclists demonstrated greater peak power outputs (~200 W) across the shorter efforts of the power profile. The data demonstrate that the road and XCMB cyclists possessed higher aerobic physiological capacities and power outputs than the DHMB and BMX cyclists. The latter disciplines possessed greater explosive power outputs. Together, these findings reflect the specificity of selected traits that are possessed within each cycling discipline.

Assessment of left ventricular preload by cardiac magnetic resonance imaging predicts exercise capacity in adult operated tetralogy of Fallot: a retrospective study.

BackgroundThe optimal timing of pulmonary homograft valve replacement (PVR) is uncertain. Cardiopulmonary exercise testing (CPET) and cardiac magnetic resonance (CMR) are often used to guide the clinical decision for PVR in operated tetralogy of Fallot (TOF) patients with significant pulmonary regurgitation (PR). We aim to study the relationship between exercise capacity and CMR in these patients.MethodsThe study is a single-centre retrospective analysis of 36 operated TOF patients [median 21.4 (interquartile range 16.4, 26.4) years post-repair; 30 NYHA I, 6 NYHA II; median age 25.2 (interquartile range 19.5-31.7) years, 29 males] with significant PR on CMR who underwent CPET within 15 [median 2.0 (interquartile range 0.8-7.2)] months from CMR. CPET parameters were compared with 30 age- and sex-matched healthy controls [median age 27.8 (interquartile range 21.0-32.8) years; 24 males].ResultsPeak systolic blood pressure (177 versus 192 mmHg, p = 0.007), Mets (7.3 versus 9.9, p < 0.001), peak oxygen consumption (VO2max) (29.2 versus 34.5 ml/kg/min, p < 0.001) and peak oxygen pulse (11.0 versus 13.7 ml/beat, p = 0.003) were significantly lower in TOF group versus control. Univariate analyses showed negative correlation between PR fraction and anaerobic threshold. There was a positive correlation between indexed left (LV) and right (RV) ventricular end-diastolic volumes, as well as indexed LV and effective RV stroke volumes, on CMR and VO2max and Mets achieved on CPET. These remained significant after adjustment for age and sex.ConclusionsTOF subjects have near normal exercise capacity but significantly lower Mets, VO2max and peak oygen pulse achieved compared to controls. Increased PR fraction in TOF subjects was associated with lower anaerobic threshold. Higher indexed effective RV stroke volume, a measure of LV preload, was associated with higher VO2max and Mets achieved, and may potentially be used as a predictor of exercise capacity.