Physiological Response To Swimming In The Flume And The Pool

Abstract

In swimming, exercise tests are performed either in the swimming pool or in the swimflume. PURPOSE The aim of this study was to compare physiological variables and the swimming economy between swimming in the flume and free swimming in the pool. METHODS In a randomized order, 18 swimmers (13 male, 5 female; age: 23.2 ± 3.6 yrs.) performed 200m incremental swim tests (at 0.95 m/s, increasing by 0.05 m/s each exercise increment, 1 min break between each exercise step) until exhaustion in the flume (f), 25m (25) and 50m (50) pool. RESULTS There were no statistically significant differences during maximal incremental test for heart rate (HR), arm stroke rate (ASR), lactate (LA) and oxygen uptake (VO2) (determined by the rebreathing method via exponential backward extrapolation). At submaximal workloads, LA, VO2 (both accounting for power output PO), HR and ASR were not different in 25 and 50 but were significantly higher in the pool compared to f (2way-ANOVA). Significantly more increments were performed in f compared to the pool performance (25: 8.0 ± 1.9; 50: 7.7 ± 1.2; f: 9.7 ± 1.5; 1way-ANOVA). During each exercise increment, performance time was longest in f and shortest in 25. PO in f was significantly lower than in free swimming. CONCLUSION By means of the equation PO = (Axv3)/(egxep) (A=drag factor, ep=propelling efficiency, eg=gross efficiency) swimming in the flume was more economical than free swimming. The difference in performance time may be attributed to the time saving turns. The higher economy in flume swimming can be explained by a smaller loss of kinetic energy due to the water movement under flume conditions and by a reduced degree of static elements although different arm stroke technique and the creation of vortices exacerbated the swimming in a swim flume. Supported by a grant from the German Federal Institute of Sport Science (BISP) under VF 0407/16/0701/99