Does Recreational Soccer Change Metabolic Syndrome Status in Obese Adolescents? A Pilot Study.

Purpose: To evaluate whether a soccer program (RSP) might lower risk factors related to metabolic syndrome (MetS) in obese adolescents. Methods: A 12-week randomized controlled trial [RSP: n = 6 (2 girls), age = 13.9 ± 1.6 yr, body mass index = 30.5 ± 2.1 kg/m2; Control: n = 7 (2 girls); age = 14.7 ± 2.3 yr, body mass index: 30.8 ± 3.1 kg/m2] was conducted. Participants underwent anthropometric, body fractioning, blood pressure, lipid profile, and glucose tolerance assessments at baseline and post-intervention. MetS status was determined based on waist circumference and at least two additional criteria: high blood pressure, hypertriglyceridemia, dyslipidemia, and hyperglycemia. RSP included eutrophic and overweight adolescents and consisted of small-sided games (85 ± 4% maximal heart rate) performed three times/week. Results: High-density lipoprotein increased [(HDL) ∆15.5 ± 5.2 mg·dL-1; p = .01] and triglycerides lowered [(TG) ∆-34.7 ± 7.1 mg·dL-1; p = .02] after RSP intervention. Between-group differences were also detected for changes in HDL (∆13.0 ± 6.1 mg·dL-1; p = .04) and TG (∆-47.1 ± 7.7 mg·dL-1; p = .05). The presence of MetS lowered in RSP (5 in 6 participants; p = .02), but not Control (1 in 7 participants; p = .32). Conclusion: A 12-week RSP was effective to reduce MetS risk factors and status in obese adolescents.

Relationship Between Percentages of Heart Rate Reserve and Oxygen Uptake Reserve During Cycling and Running: A Validation Study.

Guimarães, GC, Farinatti, PTV, Midgley, AW, Vasconcellos, F, Vigário, P, and Cunha, FA. Relationship between percentages of heart rate reserve and oxygen uptake reserve during cycling and running: a validation study. J Strength Cond Res 33(7): 1954-1962, 2019-This study investigated the relationship between percentages of heart rate reserve (%HRR) and oxygen uptake reserve (%VO2R) during a cardiopulmonary exercise test (CPET) and discrete bouts of isocaloric cycling and treadmill running. Thirty men visited the laboratory 3 times for anthropometrical and resting VO2 assessments, and perform cycling and running CPETs. Ten men visited the laboratory twice more to investigate the validity of the %HRR-%VO2R relationships during isocaloric bouts of cycling and running at 75% VO2R with energy expenditures of 400 kcals. The %HRR was significantly higher than the %VO2R during both CPETs at all exercise intensities (p < 0.001). During isocaloric exercise bouts, mean %HRR-%VO2R differences of 6.5% and 7.0% were observed for cycling and running, respectively (p = 0.007-p < 0.001). The %HRR and %VO2R increased over time (p < 0.001), the rate of which was influenced by exercise modality (p < 0.001). On average, heart rate was 5 (p = 0.007) and 8 (p < 0.001) b·min higher than predicted from the second energy expenditure quartile for cycling and running, respectively; however, observed VO2 was lower than predicted during all quartiles for cycling, and the first quartile for running. Consequently, time to achieve the target energy expenditure was greater than predicted (p < 0.01). In conclusion, the %HRR-%VO2R relationship observed during CPET data did not accurately transpose to prolonged isocaloric bouts of cycling and running. In addition, power outputs and speeds defined by the American College of Sports Medicine equations for cycling and running, respectively, overestimated VO2 and energy expenditure.

Continuous and Accumulated Bouts of Cycling Matched by Intensity and Energy Expenditure Elicit Similar Acute Blood Pressure Reductions in Prehypertensive Men.

Fonseca, GF, Farinatti, PTV, Midgley, AW, Ferreira, A, de Paula, T, Monteiro, WD, and Cunha, FA. Continuous and accumulated bouts of cycling matched by intensity and energy expenditure elicit similar acute blood pressure reductions in prehypertensive men. J Strength Cond Res 32(3): 857-866, 2018-This study investigated differences in postexercise hypotension (PEH) after continuous vs. accumulated isocaloric bouts of cycling. Ten prehypertensive men, aged 23-34 years, performed 2 bouts of cycling at 75% oxygen uptake reserve, with total energy expenditures of 400 kcal per bout. One exercise bout was performed continuously (CONTIN) and the other as 2 smaller bouts each expending 200 kcal (INTER1 and INTER2). Systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), and cardiac autonomic control were monitored in a supine position for 10 minutes before and 60 minutes after each exercise bout, and during a control session. Compared with control, blood pressure was significantly reduced after CONTIN (SBP: [INCREMENT] - 3.4 mm Hg, p < 0.001; MAP: [INCREMENT] - 2.5 mm Hg, p = 0.001), INTER1 (SBP: [INCREMENT] - 2.2 mm Hg, p = 0.045), and INTER2 (SBP: [INCREMENT] - 4.4 mm Hg, p < 0.001; DBP: [INCREMENT] - 2.7 mm Hg, p = 0.045; MAP: [INCREMENT] - 3.3 mm Hg, p = 0.001). The PEH was similar in CONTIN and INTER2, whereas INTER2 elicited greater PEH than INTER1 (SBP and MAP: [INCREMENT] - 2.0 and [INCREMENT] - 1.8 mm Hg, respectively, p ≤ 0.05). Increases in sympathovagal balance from baseline were inversely related to changes in SBP and DBP after CONTIN and INTER2 (r = -0.64 to -0.71; p = 0.021-0.047). These findings indicate that similar amounts of PEH are observed when exercise is performed as a single 400-kcal exercise bout or 2 × 200-kcal bouts and that the exercise recovery pattern of cardiac autonomic activity may be important in eliciting PEH.

Standardized MET Value Underestimates the Energy Cost of Treadmill Running in Men.

The main purpose of the present study was to compare the reference metabolic equivalent (MET) value and observed resting oxygen uptake (VO2) for defining cardiorespiratory fitness (VO2max) and characterizing the energy cost of treadmill running. A heterogeneous cohort of 114 healthy men volunteered to participate. In Part 1 of the study, 114 men [mean±SD, age: 24±5 years; height: 177.1±7.9 cm; body mass: 75.0±10.0 kg] visited the laboratory twice for assessment of resting and maximal VO2 values to compare the reference MET value vs. observed resting VO2 and to investigate the association between resting VO2 and VO2max. In Part 2, 14 of the 114 men visited the laboratory once more to perform a 30-min bout of running at 8.0 km∙h-1/8.3 METs. The mean observed resting VO2 of 3.26 mL·kg-1·min-1 was lower than the reference MET value of 3.5 mL·kg-1·min-1 (P<0.001). Resting and maximal VO2 values relative to total body mass and fat-free mass were positively correlated (R=0.71 and 0.60, respectively; P<0.001). The maximal MET and energy cost of treadmill running were consequently underestimated when calculated using the reference MET value only for those with low VO2max (P=0.005 to P<0.001). In conclusion, the reference MET value considerably overestimated observed resting VO2 in men with low VO2max, resulting in underestimations of the maximal MET, exercise intensity prescription, and the energy cost of running.

Normalizing handgrip strength in older adults: An allometric approach.

PURPOSE: Handgrip strength is an important variable to assess as part of any health intervention among older adults. Although the use of allometric normalization is the appropriate approach for removing the body size effect in handgrip performance, the best body size variable for this normalization is still unclear. Therefore, the aim of the present study was to compare the use of three body size variables (body mass, fat-free mass and body height) in allometric normalization for Handgrip strength among older adults. METHODS: Data from individuals admitted to the Elderly Care Center of the Open University of the Third Age were used, the sample consisting of 263 individuals (140 women), aged between 60-87. RESULTS: The results provided allometric exponents for normalization of HGS in each body size variable (body mass: 0.31; fat-free mass: 0.11; body height: 0.46). The correlations between normalized HGS and body size variables were significant (p<0.05) when HGS were normalized by body mass or fat-free mass. On the contrary, no significant correlations were found when HGS were normalized by body height. CONCLUSIONS: Body height seems to be the best body size variable for performing allometric normalization of HGS among older adults.

Blood pressure and autonomic responses following isolated and combined aerobic and resistance exercise in hypertensive older women.

PURPOSE: This study aimed to compare blood pressure (BP) after isolated and combined sessions of aerobic and resistance exercises in hypertensive older women. Heart rate (HR) and heart rate variability (HRV) were included as additional variables. METHODS: Twenty-one older women (63±1.9 years; 69.9±2.7 kg; 158.8±2.1 cm) with controlled hypertension (resting BP = 132.2 ± 3.1/74.1 ± 4.0 mmHg) performed four random sessions on different days: 1) aerobic exercise (AE: treadmill walking/running; 40 min; 50-60% HRreserve); 2) resistance exercise (RE: 8 exercises; 3 sets; 15 reps; 40% 1RM)); 3) aerobic exercise followed by resistance exercise (A+R); 4); control (CON). BP, HR and HRV were measured at rest and during 180 min after the sessions. RESULTS: The AE and A+R sessions demonstrated significant decreases in SBP and DBP (30, 60, 120, and 180 min; P < 0.05) and increases in HR (30 and 60 min; P < 0.05) compared to the CON. The RE session demonstrated significant reductions compared to the CON only for DBP (120 and 180 min; P < 0.05). No significant differences were observed in HRV between resting and all sessions. CONCLUSION: All sessions that involved aerobic exercise (AE and A+R) caused postexercise hypotension in comparison to the CON, with no differences in HRV.

Dynamic Resistance Training as Stand-Alone Antihypertensive Lifestyle Therapy: A Meta-Analysis.

BACKGROUND: Aerobic exercise (AE) is recommended as first-line antihypertensive lifestyle therapy based on strong evidence showing that it lowers blood pressure (BP) 5 to 7 mm Hg among adults with hypertension. Because of weaker evidence showing that dynamic resistance training (RT) reduces BP 2 to 3 mm Hg among adults with hypertension, it is recommended as adjuvant lifestyle therapy to AE training. Yet, existing evidence suggests that dynamic RT can lower BP as much or more than AE. METHODS AND RESULTS: We meta-analyzed 64 controlled studies (71 interventions) to determine the efficacy of dynamic RT as stand-alone antihypertensive therapy. Participants (N=2344) were white (57%), middle-aged (47.2±19.0 years), and overweight (26.8±3.4 kg/m(2)) adults with prehypertension (126.7±10.3/76.8±8.7 mm Hg); 15% were on antihypertensive medication. Overall, moderate-intensity dynamic RT was performed 2.8±0.6 days/week for 14.4±7.9 weeks and elicited small-to-moderate reductions in systolic BP (SBP; d+=-0.31; 95% CIs, -0.43, -0.19; -3.0 mm Hg) and diastolic BP (DBP; d+=-0.30; 95% CIs, -0.38, -0.18; -2.1 mm Hg) compared to controls (Ps<0.001). Greater BP reductions occurred among samples with higher resting SBP/DBP: ≈6/5 mm Hg for hypertension, ≈3/3 mm Hg for prehypertension, and ≈0/1 mm Hg for normal BP (Ps<0.023). Furthermore, nonwhite samples with hypertension experienced BP reductions that were approximately twice the magnitude of those previously reported following AE training (-14.3 mm Hg [95% CIs, -19.0, -9.4]/-10.3 mm Hg [95% CIs, -14.5, -6.2]). CONCLUSIONS: Our results indicate that for nonwhite adult samples with hypertension, dynamic RT may elicit BP reductions that are comparable to or greater than those reportedly achieved with AE training. Dynamic RT should be further investigated as a viable stand-alone therapeutic exercise option for adult populations with high BP.

Effect of continuous and intermittent bouts of isocaloric cycling and running exercise on excess postexercise oxygen consumption.

OBJECTIVES: The purpose of this study was to investigate excess postexercise oxygen consumption (EPOC) induced by isocaloric bouts of continuous and intermittent running and cycling exercise. DESIGN: This was a counterbalanced randomized cross-over study. METHODS: Ten healthy men, aged 23-34yr, performed six bouts of exercise: (a) two maximal cardiopulmonary exercise tests for running and cycling to determine exercise modality-specific peak oxygen uptake (VO2peak); and (b) four isocaloric exercise bouts (two continuous bouts expending 400kcal and two intermittent bouts split into 2×200kcal) performed at 75% of the running and cycling oxygen uptake reserve. Exercise bouts were separated by 72h and performed in a randomized, counter-balanced order. The VO2 was monitored for 60-min postexercise and for 60-min during a control non-exercise day. RESULTS: The VO2 was significantly greater in all exercise conditions compared to the control session (P<0.001). The combined magnitude of the EPOC from the two intermittent bouts was significantly greater than that of the continuous cycling (mean difference=3.5L, P=0.001) and running (mean difference=6.4L, P<0.001). The exercise modality had a significant effect on net EPOC, where running elicited a higher net EPOC than cycling (mean difference=2.2L, P<0.001). CONCLUSIONS: Intermittent exercise increased the EPOC compared to a continuous exercise bout of equivalent energy expenditure. Furthermore, the magnitude of EPOC was influenced by exercise modality, with the greatest EPOC occurring with isocaloric exercise involving larger muscle mass (i.e., treadmill running vs. cycling).

Hemodynamic responses during and after multiple sets of stretching exercises performed with and without the Valsalva maneuver.

OBJECTIVE: This study investigated the acute hemodynamic responses to multiple sets of passive stretching exercises performed with and without the Valsalva maneuver. METHODS: Fifteen healthy men aged 21 to 29 years with poor flexibility performed stretching protocols comprising 10 sets of maximal passive unilateral hip flexion, sustained for 30 seconds with equal intervals between sets. Protocols without and with the Valsalva maneuver were applied in a random counterbalanced order, separated by 48-hour intervals. Hemodynamic responses were measured by photoplethysmography pre-exercise, during the stretching sets, and post-exercise. RESULTS: The effects of stretching sets on systolic and diastolic blood pressure were cumulative until the fourth set in protocols performed with and without the Valsalva maneuver. The heart rate and rate pressure product increased in both protocols, but no additive effect was observed due to the number of sets. Hemodynamic responses were always higher when stretching was performed with the Valsalva maneuver, causing an additional elevation in the rate pressure product. CONCLUSIONS: Multiple sets of unilateral hip flexion stretching significantly increased blood pressure, heart rate, and rate pressure product values. A cumulative effect of the number of sets occurred only for systolic and diastolic blood pressure, at least in the initial sets of the stretching protocols. The performance of the Valsalva maneuver intensified all hemodynamic responses, which resulted in significant increases in cardiac work during stretching exercises.

Postexercise hypotension after maximal short-term incremental exercise depends on exercise modality.

This study investigated postexercise hypotension (PEH) after maximal cardiopulmonary exercise testing (CPET) performed using different exercise modalities. Twenty healthy men (aged 23 ± 3 years) performed 3 maximal CPETs (cycling, walking, and running), separated by 72 h in a randomized, counter-balanced order. Systolic (SBP) and diastolic blood pressure (DBP), heart rate, cardiac output, systemic vascular resistance (SVR), autonomic function (spontaneous baroreflex sensitivity (BRS) and heart rate variability (HRV)), and energy expenditure (EE) were assessed during a 60-min nonexercise control session and for 60 min immediately after each CPET. Total exercise volume (EE during CPET plus 60 min recovery) was significantly higher in running versus cycling and walking CPETs (P ≤ 0.001). Compared with control, only SBP after running CPET was significantly reduced (Δ = -6 ± 8 mm Hg; P < 0.001). Heart rate and cardiac output were significantly increased (P < 0.001) and SVR significantly decreased (P < 0.001) postexercise. BRS and HRV decreased after all CPETs (P < 0.001), whereas sympatho-vagal balance (low- and high-frequency (LF:HF) ratio) increased significantly after all exercise conditions, especially after running CPET (P < 0.001). Changes in SVR, BRS, sympathetic activity (low-frequency component of HRV), and LF:HF ratio were negatively correlated to variations in SBP (range -0.69 to -0.91; P < 0.001) and DBP (range -0.58 to -0.93; P ≤ 0.002). These findings suggest that exercise mode or the total exercise volume are major determinants of PEH magnitude in healthy men. Because of the running CPET, the PEH was primarily related to a decrease in SVR and to an increase in sympatho-vagal balance, which might be a reflex response to peripheral vasodilatation after exercise.

Hemodynamic responses during and after multiple sets of stretching exercises performed with and without the Valsalva maneuver

OBJECTIVE: This study investigated the acute hemodynamic responses to multiple sets of passive stretching exercises performed with and without the Valsalva maneuver. METHODS: Fifteen healthy men aged 21 to 29 years with poor flexibility performed stretching protocols comprising 10 sets of maximal passive unilateral hip flexion, sustained for 30 seconds with equal intervals between sets. Protocols without and with the Valsalva maneuver were applied in a random counterbalanced order, separated by 48-hour intervals. Hemodynamic responses were measured by photoplethysmography pre-exercise, during the stretching sets, and post-exercise. RESULTS: The effects of stretching sets on systolic and diastolic blood pressure were cumulative until the fourth set in protocols performed with and without the Valsalva maneuver. The heart rate and rate pressure product increased in both protocols, but no additive effect was observed due to the number of sets. Hemodynamic responses were always higher when stretching was performed with the Valsalva maneuver, causing an additional elevation in the rate pressure product. CONCLUSIONS: Multiple sets of unilateral hip flexion stretching significantly increased blood pressure, heart rate, and rate pressure product values. A cumulative effect of the number of sets occurred only for systolic and diastolic blood pressure, at least in the initial sets of the stretching protocols. The performance of the Valsalva maneuver intensified all hemodynamic responses, which resulted in significant increases in cardiac work during stretching exercises. .

Effects of high intensity interval versus moderate continuous training on markers of ventilatory and cardiac efficiency in coronary heart disease patients.

BACKGROUND: We tested the hypothesis that high intensity interval training (HIIT) would be more effective than moderate intensity continuous training (MIT) to improve newly emerged markers of cardiorespiratory fitness in coronary heart disease (CHD) patients, as the relationship between ventilation and carbon dioxide production (VE/VCO2 slope), oxygen uptake efficiency slope (OUES), and oxygen pulse (O2P). METHODS: Seventy-one patients with optimized treatment were randomly assigned into HIIT (n = 23, age = 56 ± 12 years), MIT (n = 24, age = 62 ± 12 years), or nonexercise control group (CG) (n = 24, age = 64 ± 12 years). MIT performed 30 min of continuous aerobic exercise at 70-75% of maximal heart rate (HRmax), and HIIT performed 30 min sessions split in 2 min alternate bouts at 60%/90% HRmax (3 times/week for 16 weeks). RESULTS: No differences among groups (before versus after) were found for VE/VCO2 slope or OUES (P > 0.05). After training the O2P slope increased in HIIT (22%, P < 0.05) but not in MIT (2%, P > 0.05), while decreased in CG (-20%, P < 0.05) becoming lower versus HIIT (P = 0.03). CONCLUSION: HIIT was more effective than MIT for improving O2P slope in CHD patients, while VE/VCO2 slope and OUES were similarly improved by aerobic training regimens versus controls.

Prediction of peak oxygen pulse (O2Ppeak) without exercise testing in older adults.

Peak oxygen pulse has been considered a surrogate of cardiovascular function and an independent predictor of all cause mortality. However, O2P(peak) depends on maximal volitional effort which may limit its utility in older subjects. The aim of this study was to develop a model to estimate O2P(peak) without exercise in an elderly sample. This cross-sectional study enrolled 67 community-dwelling older adults (69.4±7.1 years; 41 men) for the non-exercise model development and 30 community-dwelling older adults (67.7±6.4 years; n=30; 17 men) for cross-validation. The non-exercise model was derived through hierarchical regression model and cross-validated by means of PRESS statistics and comparison against an independent sample. Classification accuracy of the model for tertiles of estimated and actual O2P(peak) was tested by gamma (γ) nonparametric correlation. The following prediction equation was generated: -3.416+0.137 × weight (kg)+1.226 × Veterans Specific Activity Questionnaire (VSAQ) (metabolic equivalents, METs)+1.987 × gender (0=women, 1=men)-2.045 × ß-Blockers use (0=no, 1=yes)-0.044 × resting heart rate (HR) (R(2)=0.83; standard error of estimate (SEE)=1.68 mL beat(-1)). Correlation in cross-validation group was 0.80 (P<0.001). A high probability was observed for the model to rank the values in the same tertile in validation and cross-validation groups (γ=0.98; γ=0.92, respectively, P<0.05). In conclusion, O2P(peak) can be estimated with reasonable precision without exercise testing, providing an alternative for elder subjects not capable to perform maximal effort.

Flexibility of the elderly after one-year practice of yoga and calisthenics.

Flexibility training responses to distinct stretching techniques are not well defined, especially in the elderly. This study compared the flexibility of elderly individuals before and after having practiced hatha yoga and calisthenics for 1 year (52 weeks), at least 3 times/week. Sixty-six subjects (12 men) measured and assigned to 3 groups: control (n = 24, age = 67.7±6.9 years), hatha yoga (n = 22, age = 61.2±4.8 years), and calisthenics (n = 20, age = 69.0±5.8 years). The maximal range of passive motion of 13 movements in 7 joints was assessed by the Flexitest, comparing the range obtained with standard charts representing each arc of movement on a discontinuous and non-dimensional scale from 0 to 4. Results of individual movements were summed to define 4 indexes (ankle+knee, hip+trunk, wrist+elbow, and shoulder) and total flexibility (Flexindex). Results showed significant increases of total flexibility in the hatha yoga group (by 22.5 points) and the calisthenics group (by 5.8 points) (p < 0.01 for each) and a decrease in the control group (by 2.1 points) (p < 0.01) after one year of intervention. Between-group comparison showed that increases in the hatha yoga group were greater than in the calisthenics group for most flexibility indexes, particularly the overall flexibility (p <0.05). In conclusion, the practice of hatha yoga (i.e., slow/passive movements) was more effective in improving flexibility compared to calisthenics (i.e., fast/dynamic movements), but calisthenics was able to prevent flexibility losses observed in sedentary elderly subjects.

Metabolic equivalent concept in apparently healthy men: a re-examination of the standard oxygen uptake value of 3.5 mL·kg(-1)·min(-1.).

This study compared resting oxygen uptake (V̇O2) with the standard metabolic equivalent (MET) value of 3.5 mL·kg(-1)·min(-1), tested the accuracy of a previously published prediction model for resting V̇O2, and proposed a new prediction model for a more homogeneous population. One hundred and twenty-five apparently healthy men, aged 17-38 years, visited the laboratory for the assessment of resting V̇O2. The mean resting V̇O2 of 3.21 mL·kg(-1)·min(-1) (95% confidence interval (CI), 3.13 to 3.30) was significantly lower than the standard MET value of 3.5 mL·kg(-1)·min(-1) (mean difference, 0.29; 95% CI, 0.20 to 0.37; t = 6.7; p < 0.001). The prediction model proposed by a previous study, derived from a heterogeneous sample, exhibited no predictive ability in our more homogeneous sample. However, our population-specific regression model, which included body surface area and percent body fat as predictors, demonstrated relatively poor predictive ability, with a low R(2) (0.22) and high standard error of the estimate (0.42 mL·kg(-1)·min(-1)). Pearson's correlation coefficients for body surface area and resting V̇O2, and for percent body fat and resting V̇O2, were 0.20 (p = 0.022) and -0.36 (p < 0.001), respectively. In conclusion, the standard MET value of 3.5 mL·kg(-1)·min(-1) considerably overestimates mean resting V̇O2 in a relatively large group of apparently healthy men. Our population-specific prediction model for resting V̇O2 demonstrated relatively poor accuracy, although it was considerably more accurate than the previously published model. Further research needs to be conducted to establish accurate population-specific prediction models.

Diagnostic accuracy of pre-exercise screening questionnaire: emphasis on educational level and cognitive status.

The physical activity readiness questionnaire (PAR-Q) has been the most popular simple method of screening for people who intend to engage in exercise programs. Despite of the recommendations indicating that the instrument should be applied in the age range from 15 to 69 years, the questionnaire has been widely used in elderly people. The aim of this study was to assess the diagnostic accuracy of PAR-Q in elderly women with respect to absolute and relative contraindications to exercise and verify the influence of educational level and cognitive status. Eighty-nine subjects (61-89 years) participated in the study and went through clinical exams and exercise testing. The influence of educational status, age and cognitive state (Mini-Mental State Examination, MMSE) on the PAR-Q responses was analyzed by logistic regression. The occurrences of absolute and relative contraindications were respectively 9% and 22%. The Sensitivity and Specificity were 75.0% and 19.8% (absolute) and 77.8% and 19.7% (relative). The PAR-Q results were not influenced by low educational status; age, or cognitive state. In conclusion, although the usefulness and easy applicability of the PAR-Q's questions, the responses to the questionnaire led to a high number of false positive and false negative cases, suggesting that it would not be adequate as a pre-participation screening tool in elder samples.

Relationships between emerging cardiovascular risk factors, z-BMI, waist circumference and body adiposity index (BAI) on adolescents.

OBJECTIVE: The body adiposity index (BAI) has been recently proposed as an alternative index to body mass index (BMI) and waist circumference (WC) to evaluate adiposity in adults, with special focus on its ability to discriminate gender specificities on adiposity. Endothelial dysfunction, circulating endothelial cells (CECs), endothelin-1 and adipocytokines are all related to atherosclerosis and nowadays considered as markers of emerging cardiovascular (CV) risk. This study aimed to determine in normal weight and obese adolescents which measures of body composition (BAI and z-BMI) or distribution (WC) correlate better with emerging CV risk markers. PATIENTS: Forty adolescents were selected according to BMI: normal weight (n = 20; 7 girls/13 boys, 14·7 ± 1·4 years, 53·4 ± 6·0 kg, z-BMI 0·6 ± 0·1) and obese ones (n = 20; 13 girls/7 boys, 14·1± 1·0 years, 86·7 ± 11·5 kg, z-BMI 2·7 ± 0·4). MEASUREMENTS: Body fat and fat mass were measured by dual-energy X-ray absorptiometry (DXA). Non-nutritive skin microvascular reactivity was evaluated by laser Doppler flowmetry with iontophoretic release of vasoactive drugs. Activated CECs were assessed by flow cytometric analysis. RESULTS: In adolescents, the measurement of % fat by DXA showed high correlation with BAI (ρ = 0·75, P < 0·0001), z-BMI (r = 0·84, P < 0·0001) and WC (r = 0·83, P < 0·0001). Endothelin-1 and activated CECs did not correlate with any anthropometric measures while adipocytokines expressed variable associations among them. Endothelium-dependent vasodilation showed higher correlation with BAI (r = -0·51, P < 0·0001) compared to z-BMI (r = -0·40, P < 0·001) or WC (r = -0·45, P < 0·001), specially on females. CONCLUSIONS: BAI was associated with emerging CV risk markers in adolescents but further research is needed to evaluate its potential in clinical and epidemiological sets.

Influence of exercise order on the number of repetitions, oxygen uptake, and rate of perceived exertion during strength training in younger and older women.

The study investigated the effect of resistance exercise order on the number of repetitions, oxygen uptake (VO(2max)) and rate perceived exertion (RPE) in younger (YG: N = 10; 22 ± 2 years; VO(2peak) 42.2 ± 2.9 ml·kg(-1)·min(-1)) and older (EG: N = 8; 69 ± 7 years; VO(2peak)22.7 ± 2.5 ml·kg(-1)·min(-1)) women. The subjects performed 3 sets of each exercise until fatigue using 10 repetition maximum in 2 sequences of opposite order: (a) sequence A (SEQA): bench press (BP), machine shoulder press (SP), pulley triceps extension (TE); (b) sequence B (SEQB): TE-SP-BP. The VO(2) was assessed during the exercises, rest intervals, and 20 minutes after sequences (postexercise oxygen consumption [EPOC]). The number of repetitions decreased in both groups (p < 0.05) throughout sets. No difference (p > 0.22) was found between sequences for total VO(2) (exercise sequences + EPOC) in YG (SEQA = 25.41 ± 6.51 L vs. SEQB = 24.81 ± 4.08 L) and EG (SEQA = 26.45 ± 5.24 L vs. SEQB = 26.91 ± 4.62 L). In both groups, the VO(2) within the sequences was higher during BP when it was placed at the end of SEQB, the same occurring with TE in SEQA (p < 0.05). The VO(2) within sequences and RPE were higher in SEQB compared with SEQA (p < 0.05) in EG but not in YG. In conclusion, the exercise order did not affect total VO(2). The VO(2) within a given sequence was always lower when an exercise was performed first as compared with last regardless of the exercise order. Accumulated fatigue reflected by the VO(2) within sequences and RPE was influenced by the exercise order only in EG, suggesting that to prevent early fatigue, resistance training sessions in this group should preferably progress from large toward small-muscle group exercises.

Effects of different resistance training frequencies on the muscle strength and functional performance of active women older than 60 years.

Training frequency is an important resistance training variable, but its relative contribution to strength and functional performance (FP) gains in senior populations is not yet well defined. The present study investigated the effect of different resistance training frequencies on the strength and FP in active women aged 60 years and older. A total of 48 women (60-78 years) underwent a 16-week training program for 1 set of 10 repetition maximums (10RMs) of each exercise, being assigned in groups that performed training frequencies of 1, 2, or 3 days per week (EG1, EG2, and EG3) and a control group. Strength and FP tests were applied before and after the training protocol. All EGs, but not the control group, exhibited 10RM increases (bench press, seated dumbbell curl, knee extension, standing calf raise, p < 0.01). The 10RM increase for seated dumbbell curl and knee extension was always greater in the higher frequencies (p < 0.05). Timed up and go test improved equally in all EGs (p < 0.01). Chair sit-and-stand improvements in EG3 (-15.7%) and EG2 (-9.8%) were greater than in EG1 (-4.6%) (p < 0.01). Gait-speed improvement in EG3 (-11.6%) was greater than in EG2 (-5.1%) and EG1 (-3.9%) (p < 0.01). In conclusion, a higher weekly training frequency increased FP and strength to a greater extent than lower frequencies in active senior women.

How long does it take to achieve steady state for an accurate assessment of resting VO2 in healthy men?

The time necessary to obtain a steady state for an accurate and reliable assessment of resting [Formula: see text] remains unclear and was the purpose of this study. Thirty healthy men, aged 17-28 years, visited the laboratory twice for the assessment of resting [Formula: see text], which was assessed as follows: (a) 24 h abstention from physical exercise, alcohol, soft drinks and caffeine, (b) fasting for at least 8 h, (c) an acclimation period of 10 min, and (d) 60 min assessment in a supine position. Resting [Formula: see text] significantly changed during the 60 min (F = 37.4, P < 0.001), exhibiting a monoexponential decrease before reaching an asymptote. Post hoc pairwise comparisons showed that significant differences existed between consecutive means until the 30 min time point, after which there were no significant differences. The [Formula: see text] response across trials exhibited high test-retest reliability, with within-subject coefficients of variations at each time point ranging from 2.8 to 7.0 % and intraclass correlation coefficients ranging from 0.90 to 0.99. The reliability was higher from the 25 min time point onwards. Based on these findings, the following recommendations are made to promote accurate assessment of resting [Formula: see text]: (a) initiate the resting [Formula: see text] measurement with 10 min of acclimation to the assessment apparatus, (b) determine resting [Formula: see text] for a minimum of 30 min, until an apparent [Formula: see text] steady state has been achieved; and (c) determine resting [Formula: see text] for a further 5 min, with the average of this last 5 min of data being regarding as the resting [Formula: see text].