SPRINT SWIMMING CAPACITIES IN AGING MASTERS SWIMMERS
Hartley, A. A., & Hartley, J. T. (1986). Age differences and changes in sprint swimming performances of masters athletes. Experimental Aging Research, 12(2), 65-70.
The decline of swimming speed with increasing age has been attributed to a decline in strength or a decline in power. This study used a repeated cross-sectional analysis of masters swimming age-groups to evaluate what was causing the decline.
There was no difference in the decline rates of 50 or 100-yd swimming events. The average speed for 100 yd as a proportion of 50-yd speed was the same across groups. This fails to support a "power decline" explanation because in the shorter event the ratio of power output to power available is greater than in the longer event. Since it has been shown that breaststroke swimming requires the greatest output of power it should be expected that breaststroke times would decline faster than the other strokes if power was the mitigating variable. This was not the case as breaststroke declined at roughly the same rate as front and back crawl. Thus, the decline in swimming speeds cannot be attributed to a loss in swimming power.
Butterfly times declined the greatest. The stop-and-go nature of the butterfly stroke requires considerable arm and shoulder strength to overcome inertia to begin the arm pull as well as the strength required for the underwater pull. Thus, it is more tenable to assert that speed decrements in masters sprint-swimming events is attributable to reduced muscle strength rather than power.
Implication. To thwart the decline in swimming muscle strength, masters swimmers should engage in land-strength work designed for the shoulders and arms to employ the muscle groups involved with swimming propulsion as well as tethered water swimming. The land work will likely have modest effects whereas the water work will be more beneficial.