Physiological Responses and Perceived Effort of Older Women When Using Different Buoyant Dumbbells in a Water Fitness Exercise: A Pilot Study

Background/Objectives: The use of buoyant equipment in water fitness sessions appears to elicit a more intense physiological response in water exercises. However, it remains unknown whether the shape of the equipment influences these responses. The present study aimed to analyze and compare the physiological responses and perceived effort while older women using different buoyant dumbbells during horizontal adduction/abduction of the upper limbs (HA exercise). Methods: Ten older women (76.1 ± 5.3 years of age) attended two assessment sessions to perform HA exercise at a music cadence of 120 bpm with different buoyant dumbbells (one pair for each session): round hydro and hydro crystal. Mean heart rate (HR), systolic and diastolic blood pressures (SBP and DBP, respectively), double product (DPr), blood lactate concentration ([La−), and rate of perceived effort (RPE) were assessed according to pre-exercise (rest), warm-up and the HA exercise (five min effort). Results: The mean HR was also analyzed according to the percentage (%) of the predicted maximal theoretical HR (HRmax). Older women reached ~56 and 61% of HRmax using crystal and round dumbbells, respectively. Differences were found in mean HR, [La−], and RPE with the round dumbbell showing greater values than the crystal dumbbell. Although no differences were found in SBP and DBP, DPr was higher when women used the round dumbbells. Conclusions: The shape of buoyant dumbbells seems to define acute responses of older women as the round dumbbell promotes a more intense physiological response and perceived effort when compared to the crystal dumbbell.