Carlo, A. C., Sikora, A. T., & Coast, J. R. (June 03, 2010) A comparison of diaphragm thickness in female swimmers, runners, and non-athletes. Presentation 2094 at the 2010 Annual Meeting of the American College of Sports Medicine, Baltimore, Maryland; June 2-5.

This study determined if female collegiate athletes training for endurance swimming and running events have thicker diaphragms than those training for sprint swimming or non-athletic Ss (overall total of Ss N = 25). The relationship between maximal inspiratory pressures and diaphragm thickness was also assessed in some Ss (N = 16). Four groups were identified (distance swim, distance run, sprint swim, and controls).

Diaphragm thickness differed among the four groups. The average diaphragm thickness of the distance swimmers was significantly more than the distance runners and the controls. There was a significant difference in diaphragm thickness between the distance and sprint swimmers. There was no significant correlation between diaphragm thickness and maximal inspiratory pressures.

Implication. The difference in diaphragm thickness between the sprint and distance swimmers supports the hypothesis that endurance-based training has the ability to cause increased diaphragm thickness (evidence of hypertrophy) when compared to sprint training. However, a significant difference in diaphragm thickness between distance swimmers and distance runners suggests sport-specific training effects.

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