Composición corporal en mujeres deportistas premenopáusicas y postmenopáusicas / Body composition in premenopausal and postmenopausal well-trained females

Objetivo: El propósito fue analizar la influencia de las hormonas sexuales en la composición corporal de deportistas con diferente estatus hormonal. Metodología: 46mujeres eumenorreicas, 41 usuarias de píldora anticonceptiva monofásica y 16mujeres postmenopáusicas bien entrenadas participaron en el estudio. Las voluntarias realizaron un Dual-energy X-ray Absorptiometry scan (DXA) y una bioimpedancia durante la fase folicular temprana y no hormonal, verificado con una analítica. Resultados: La prueba ANCOVA no mostró diferencias ni en las variables medidas con DXA (peso, masa grasa androide y ginoide, masa grasa total y masa libre de grasa) ni en las de bioimpedancia (peso, masa grasa, masa libre de grasa y agua corporal total). Conclusión: Las hormonas sexuales parecen no influir en la composición corporal de mujeres activas. Las mujeres postmenopáusicas activas presentan una distribución de masa grasa similar a las premenopáusicas, lo que podría explicarse por el efecto positivo de la actividad física. (AU)

Purpose: The aim was to analyse the influence of sex hormones on body composition in well-trained females with different hormonal environments.Methods: Sixty-six eumenorrheic, forty-one low-dose-monophasic oral contraceptive users and sixteen postmenopausal well-trained females participated in this study. Volunteers underwent a Dual-energy X-ray Absorptiometry scan (DXA) and a bioimpedance during the early-follicular and the withdrawal phase, verified with blood samples.Results: ANCOVA test reported no differences neither in DXA measurements (weight, fat free mass, fat mass, android and gynoid fat mass) nor in bioimpedance variables (weight, fat free mass, fat mass and total body water) among study groups.Conclusion: Sex hormones seems not to influence body composition in active women. Curiously, premenopausal and postmenopausal active women present the same fat mass distribution. It could be explained by the positive effect exercise has on body composition, and this in turn on preventing cardiovascular and metabolic diseases in this population. (AU)

The midpoint between ventilatory thresholds approaches maximal lactate steady state intensity in amateur cyclists.

The aim was to determine whether the midpoint between ventilatory thresholds (MPVT) corresponds to maximal lactate steady state (MLSS). Twelve amateur cyclists (21.0 ± 2.6 years old; 72.2 ± 9.0 kg; 179.8 ± 7.5 cm) performed an incremental test (25 W·min-1) until exhaustion and several constant load tests of 30 minutes to determine MLSS, on different occasions. Using MLSS determination as the reference method, the agreement with five other parameters (MPVT; first and second ventilatory thresholds: VT1 and VT2; respiratory exchange ratio equal to 1: RER = 1.00; and Maximum) was analysed by the Bland-Altman method. The difference between workload at MLSS and VT1, VT2, RER=1.00 and Maximum was 31.1 ± 20.0, -86.0 ± 18.3, -63.6 ± 26.3 and -192.3 ± 48.6 W, respectively. MLSS was underestimated from VT1 and overestimated from VT2, RER = 1.00 and Maximum. The smallest difference (-27.5 ± 15.1 W) between workload at MLSS and MPVT was in better agreement than other analysed parameters of intensity in cycling. The main finding is that MPVT approached the workload at MLSS in amateur cyclists, and can be used to estimate maximal steady state.

Heart rate recovery in elite Spanish male athletes.

AIM: During postexercise recovery, heart rate (HR) initially falls rapidly, followed by a period of slower decrease, until resting values are reached. The aim of the present work was to examine the differences in the recovery heart rate (RHR) between athletes engaged in static and dynamic sports. METHODS: The study subjects were 294 federated sportsmen competing at the national and international level in sports classified using the criteria of Mitchell et al. as either prevalently static (N.=89) or prevalently dynamic (N.=205). Within the dynamic group, the subjects who practised the most dynamic sports were assigned to further subgroups: triathlon (N.=20), long distance running (N.=58), cycling (N.=28) and swimming (N.=12). All athletes were subjected to a maximum exertion stress test and their HR recorded at 1, 2, 3 and 4 min (RHR1,2,3,4) into the HR recovery period. The following indices of recovery (IR) were then calculated: IR1=(HRpeak-RHR1,2,3,4)/(HRmax-HRrest)*100, IR2=(HRpeak-RHR1,2,3,4)/(HRmax/HRpeak), and IR3=HRpeak-RHR1,2,3,4. The differences in the RHR and IR for the static and dynamic groups were examined using two way ANOVA. RESULTS: The RHR at minutes 2 (138.7±15.2 vs. 134.8±14.4 beats·min⁻¹) and 3 (128.5±15.2 vs. 123.3±14.4 beats·min⁻¹) were significantly higher for the static group (Group S) than the dynamic group (Group D), respectively. Significant differences were seen between Group D and S with respect to IR1 at minutes 1 (26.4±8.7 vs. 24.8±8.4%), 2 (43.8±8.1 vs. 41.5±7.8%), 3 (52.1±8.3 vs. 49.1±8%) and 4 (56.8±8.6 vs. 55.4±7.4%) of recovery. For IR2, significant differences were seen between the same groups at minutes 2 (59.7±12.5 vs. 55.9±10.8 beats·min⁻¹) and 3 (71.0±13.5 vs. 66.1±11.4 beats·min⁻¹) of recovery. Finally, for IR3, the only significant difference between Group D and S was recorded at minute 3 of recovery (72.2±12.5 vs. 66.2±11.5 beats·min⁻¹). CONCLUSION: This work provides information on RHR of a large population of elite Spanish athletes, and shows marked differences in the way that HR recovers in dynamic and static sports.

Effects of dietary restriction combined with different exercise programs or physical activity recommendations on blood lipids in overweight adults.

BACKGROUND AND AIM: Many exercise studies, although generally showing the beneficial effects of supervised aerobic, resistance or combined exercise on blood lipids, have sometimes reached equivocal conclusions. The aim of this study is to evaluate the impact of different programs that combined exercise and dietary restriction on blood lipids versus a clinical practice intervention for weight loss, in overweight adults. METHODS: For this study 66 subjects participated in a supervised 22 weeks training program, composed of three sessions per week and they were randomized in three groups: strength training (S; n = 19), endurance training (E; n = 25), a combination of E and S (SE; n = 22). Eighteen subjects served as physical activity group (PA) that followed a clinical intervention consisted of physical activity recommendations. All groups followed the same dietary treatment, and blood samples were obtained for lipids measurements, at the beginning and end of the study. RESULTS: Lipid profile improved in all groups. No significant differences for baseline and post-training values were observed between groups. In general, SE and PA decreased low-density lipoprotein cholesterol (LDL-C) values (p < 0.01). S decreased triglyceride levels (p < 0.01) and E, SE, and PA decreased total cholesterol levels (p < 0.05, p < 0.01 and p < 0.01, respectively). CONCLUSIONS: These results suggest that an intervention program of supervised exercise combined with diet restriction did not achieved further improvements in blood lipid profile than diet restriction and physical activity recommendations, in overweight adults. (Clinical Trials gov number: NCT01116856).

Validation of the SenseWear armband in circuit resistance training with different loads.

The use of the SenseWear™ armband (SWA), an objective monitor of physical activity, is a relatively new device used by researchers to measure energy expenditure. These monitors are practical, relatively inexpensive and easy-to-use. The aim of the present study was to assess the validity of SWAs for the measurement of energy expenditure (EE) in circuit resistance training (CRT) at three different intensities in moderately active, healthy subjects. The study subjects (17 females, 12 males) undertook CRT at 30, 50 and 70% of the 15 repetition maximum for each exercise component wearing an SWA as well as an Oxycon Mobile (OM) portable metabolic system (a gold standard method for measuring EE). The EE rose as exercise intensity increased, but was underestimated by the SWAs. For women, Bland-Altman plots showed a bias of 1.13 ± 1.48 METs and 32.1 ± 34.0 kcal in favour of the OM system, while for men values of 2.33 ± 1.82 METs and 75.8 ± 50.8 kcal were recorded.