Understanding the Effect of Age on Force Production and Symmetry during Water Exercises: Differences between Young Adults and Older Women

Abstract

Participants from across the age span participate in water fitness sessions. This challenges instructors to create proper exercise prescriptions. The aim of this study was to understand the effect of age on force production and symmetry during water exercises. Twenty-six women were categorized into two groups: (i) young adult (n = 13; 23.61 ± 1.15 years) and (ii) older (n = 13; 67.38 ± 3.48 years). Women performed a horizontal upper limbs adduction during an incremental protocol comprising four music cadences increased every 30 s (105, 120, 135, and 150 b∙min−1). A differential pressure system composed of two sensors was used to measure the in-water force and to estimate the symmetry index. Young adults showed higher in-water forces (43–67 N) when compared with their older counterparts (31–55 N). No differences were observed between groups for the symmetry index. The cadences of 105–120 and 120–135 lead to different in-water force of the dominant limb in both groups, while the force of the non-dominant limb showed mix-findings. In conclusion, water fitness instructors should be aware that the same music cadence may trigger different kinetic behaviors in different ages, but without impairing symmetry when exercising at 120–135 b∙min−1.

Keywords

• biomechanics
• pressure sensors
• asymmetries
• cadence
• head-out aquatic exercises