AGE-RELATED SWIMMING PERFORMANCE DECLINE IS ASSOCIATED WITH A DECLINE IN VO2max NOT ECONOMY
Boggs, G. W., Dickinson, J. M., Nethery, V. M., Horsley, J., & D'Acquisto, L. J. (2006). Physiological comparison of younger and older trained male swimmers. Medicine and Science in Sports and Exercise, 38(5), Supplement abstract 1557.
This study compared the metabolic and cardiovascular responses in young (N = 14; age = 20.0 ± 2.2 yr), middle-aged (N = 8; age = 42.8 ± 4.9 yr), and older (N = 9; age = 56.2 ± 5.6 yr) trained male swimmers during freestyle swimming. Expired air was collected during a series of submaximal and one incremental freestyle swim to exhaustion. Heart rate was monitored and blood lactate determination was performed after each swim. Interpolation was employed to determine swimming velocity at a blood lactate of 4.0 mmol. Velocities for the final 182.9 and 68.6 m of the maximum swim were used as swimming performance measures. The age-grouped Ss were compared on selected physiological parameters at a given metabolic power of 800 watts (W) and at 70% max oxygen uptake (VO2max).
Swimming performance for the final 182.9 and 68.6 m of the maximum swim declined with advancing age. VO2max decreased with age with the greatest difference between the two older groups. Velocity and VO2max were correlated; r = .70 for the 182.9 m and r = .68 for the 68.6 m swimming performances. The maximum heart rate of the oldest Ss was 10% lower than the youngest Ss and 6% lower than the middle-aged Ss. Peak blood lactate was similar among age groups. Swimming velocity and heart rate at a given submaximal metabolic power of 800 W were similar among age groups. Metabolic power corresponding to a relative intensity of 70% VO2max and corresponding swimming velocities declined significantly with age. For all groups, velocity at a blood lactate of 4.0 mmol corresponded to the same relative physiological intensity (~68% VO2max). However, swimming velocity at a blood lactate of 4.0 mmol decreased significantly with age.
Implication. Age-related freestyle swimming performance decrements are attributable a decline in VO2max and not to any changes in swimming economy. To sustain a given velocity with advancing age, swimming at a greater relative physiological intensity would be needed to generate the required mechanical power output.