Comparação das respostas cardiorrespiratórias de um exercício de hidroginástica com e sem deslocamento horizontal nos meios terrestre e aquático Comparisons of cardiorrespiratory responses in a hydrogymnastics exercise with and without horizontal movement on land and in aquatic environment

O objetivo do estudo foi comparar as respostas cardiorrespiratórias de um exercício de hidroginástica (corrida estacionária) realizado com e sem deslocamento horizontal no meio terrestre (MT), em piscina funda (PF) e em piscina rasa (PR). Seis mulheres jovens realizaram os exercícios durante 4 min numa cadência de 80 bpm. O exercício consistia em flexão e extensão de quadril com os braços simulando um movimento de corrida. A frequência cardíaca (FC) e o consumo de oxigênio (VO2 ) foram coletados no último minuto de exercício e a percepção de esforço (PE) foi coletada ao término do exercício. Para a comparação das variáveis utilizou-se ANOVA two-way para medidas repetidas com fatores meio e forma de execução (p < 0,05). Para todas as variáveis analisadas foram encontrados valores menores no exercício em PR comparado ao exercício no MT. Porém, nenhuma diferença foi observada entre o exercício no MT e em PF, exceto para a FC, que foi menor no exercício em PF. Em relação à forma de execução, para a FC, foram encontrados valores maiores no exercício com deslocamento quando comparado ao exercício sem deslocamento somente na PF. Estes achados sugerem a possibilidade de executar o exercício analisado em PF com gasto energético (GE) similar e FC menor quando comparado ao mesmo exercício no MT. Fato de grande relevância para populações que querem obter um GE semelhante ao exercício no MT, mas que necessitam de uma menor sobrecarga cardiovascular.<br>The aim of the study was to compare the cardiorespiratory responses during an hydrogymnastics exercise performed with and without horizontal movement on land environment (LE) and in a deep (DS) and in a shallow swimming pool (SS). Six YOUNG women performed the exercise during four minutes in each environment (LE, DS and SS) and situation (with and without horizontal movement) in a cadence of 80 bpm. The exercise consisted in a hip flexion/extension while the arms simulating a running movement. The heart rate (HR) and oxygen uptake (VO2 ) were veriefied during the last minute in each exercise and the rate of perceived exertion (RPE) was collected in the ending of the exercise. To variables comparisons was used ANOVA two-way for repeated measures with factors environment and situation (p < 0,05). For all cardiorespiratory variables analyzed, SS exercise were lower than that found on LE. Although, no difference was observed in the exercise performed on LE or in DS, except for the HR, that was lower during DS. Acording to the different situations, higher HR value was found during the exercise with horizontal movement when compared with the exercise without horizontal movement in the DS. These findings suggest the possibility to perform the exercise analyzed with similar energy expenditure and lower FC in DS when compared with exercise in LE. It is very important for people that need similar energy expenditure and lower cardiovascular overload during aquatic exercise

Fluid-Electrolyte Balance Associated with Tennis Match Play in a Hot Environment

Twenty (12 male and 8 female) tennis players from two Division I university tennis teams performed three days of round-robin tournament play (i.e., two singles tennis matches followed by one doubles match per day) in a hot environment (32.2 ±and 53.9 ± 2.4% rh at 1200 hr), so that fluid-electrolyte balance could be evaluated. During singles play, body weight percentage changes were minimal and were similar for males and females (males -1.3 ± 0.8%, females -0.7 ± 0.8%). Estimated daily losses (mmol ·) of sweat sodium (Na+) and potassium (K+) (males,158.7,31.3; females,86.5,18.9) were met by the players' daily dietary intakes (mmol ·) of these electrolytes (males,279.1 ± 109.4,173.5 ± 57.7; females,178.9 ± 68.9,116.1 ± 37.5). Daily plasma volume and electrolyte (Na+,) levels were generally conserved, although, plasma [Na+] was lower (p< .05) on the morning of Day 4. This study indicated that these athletes generally maintained overall fluid-electrolyte balance, in response to playing multiple tennis matches on 3 successive days in a hot environment, without the occurrence of heat illness