RESUMEN
ABSTRACT The purpose of this study was to analyze the impact of running in normal relative humidity (RH = 53%) and very high RH (94%) on hydration status (HS), sweating rate (SR), heart rate (HR), and rating of perceived exertion (RPE). Fourteen men (25.2 ± 6.6 yrs) performed two sessions of treadmill running. Body mass (normal RH: -1.35%, very high RH: -1.65%) HS (normal RH: -14.8%; very high RH: -20.8%) were reduced while RPE (normal RH: +26%; very high RH: +28%) and HR were increased (very high RH: +5.8%: 20-40 min, +3.1%: 40-60 min, +3%: 20-40 min; +2.3%: 40-60 min for normal RH). As expected, SR was significantly greater during very high RH (-20/8%) compared to normal RH (-14.8%). Running in very high RH at moderate temperature has a greater negative impact on SR, HS, body mass, HR, RPE in men than running in normal RH at the same temperature, which places the runner in greater danger of heat illnesses such as heat exhaustion or heat stroke.
RESUMO Analisar o impacto da corrida em diferentes humidade relativa (HR) (normal (53%), muito alto (94%)), estado de hidratação (EH), taxa de transpiração (TT), freqüência cardíaca (FC), esforço percebido (RPE). Quatorze homens (25,2 anos) realizaram duas sessões de corrida em esteira. Massa corporal (HR normal: -1,35%, HR muito alta: -1,65%) e EH reduziram (HR normal: -14,8%, HR muito alta: -20,8%), RPE (HR normal: + 26%, HR muito alta: + 28%), aumento da FC (HR muito alta: + 5.8%: 20-40 min, + 3.1%: 40-60 min, HR normal: + 3%: 20-40 min; + 2.3%: 40-60 min). TT foi significantemente diferente entre HR (HR normal: -14.8%, HR muito alta: -20.8%). Há um impacto negativo na corrida em EH, massa corporal, FC e RPE em homens com HR normal e muito alta, e TT é mais afetada com HR muito alta.
RESUMEN El objetivo de este estudio fue analizar las repercusiones de correr con diferentes niveles de humedad relativa (HR) (normal [53%], muy alta [94%]) sobre el estado de hidratación (EH), la tasa de sudoración (TS), la frecuencia cardíaca (FC) y el esfuerzo percibido (EP). Catorce hombres (25,2 ± 6,6 años) realizaron dos sesiones en cinta de correr. La masa corporal (HR normal: -1,35%; HR muy alta: -1,65%) y el EH (HR normal: -14,8%; HR muy alta: -20,8%) se redujeron, mientras que el EP (HR normal: +26%; HR muy alta: +28%) y la FC (HR muy alta: +5,8%: 20-40 min; +3,1%: 40-60 min; HR normal: + 3%: 20-40 min; + 2,3%: 40-60) aumentaron. La TS fue considerablemente diferente entre las HR (HR normal: -14,8%; muy alta HR: -20,8%). Hay repercusiones negativas por correr con una HR muy alta y una temperatura moderada en TS, EH, masa corporal, FC y EP en corredores que corren a una HR normal a la misma temperatura, lo que sitúa a estos en gran peligro de sufrir un enfermedad provocada por el calor, como agotamiento por calor o golpe de calor.
RESUMEN
The main purpose of this study was to compare the effects of resistance training (RT) performed with different training volumes on phase angle (PhA), body water components, and muscle quality (MQ) in untrained older adult women. A second purpose was to assess the relationship between PhA and MQ. Sixty-two older adult women (68.6 ± 5.0 years, 65.2 ± 13.3 kg, 156.1 ± 6.2 cm) were randomly assigned into one of the three groups: two training groups performed either 1 set (G1S) or 3 sets (G3S), or a control group (CG). Body water components and PhA were estimated by bioelectrical impedance (BIA). MQ was determined by dividing skeletal muscle mass estimated by dual-energy absorptiometry (DXA) by total muscle strength from three exercises. After the intervention period, both training groups demonstrated improvements (P < 0.05) when compared with CON for intracellular water, total body water, PhA, and MQ. These results suggest that RT can improve PhA, body water components, and MQ after 12 weeks of RT in untrained older women, regardless of training volume. Furthermore, changes in MQ were positively correlated with changes in PhA (r = 0.60, P < 0.01).
