Cardiorespiratory alterations in 9 to 11 years old children following a season of competitive swimming.

The purpose of this study was to describe cardiorespiratory alterations in a group of perviously untrained 9-to-11 year old children resulting from seven months of swimming training. Fifteen members of a competitive swim team served as subjects. A non-training group of fifteen children of similar age, height and weight were studied at the same times. All measurements were made on three separate days both before and after the training period. On Measurement Day One the subjects were measured for VC, FEV1.0, and MVV. On MEasurement Day Two they were measured for PWC170 and on MEasurement Day Three height (cm), weight (kg), VE max (1/min), Vo2 max (ml/kg.min) and HR max were determined. Results of the analyses indicated that: (1) the mean PWC170 change in the trained children (+80.00 kgm/min) was significantly greater than that in the reference group (+30.00 kgm/min) (P less than .05); (2) the mean Vo2 max change in the experimental group (+8.411 ml/kg.min) was significantly greater than in the reference group (2.21 ml/kg.min) (P less than .01); and the mean changes in VC, FEV1.0, MVV, VE max, and HR max were not greater than one would expect to see in normal children of similar age and body dimensions (P greater than .05).