In-season changes in heart rate recovery are inversely related to time to exhaustion but not aerobic capacity in rowers

Abstract

To determine if in-season changes in heart rate recovery (HRR) are related to aerobic fitness and performance in collegiate rowers. Twenty-two female collegiate rowers completed testing before and after their competitive season. Body fat percentage (BF%) was determined by dual-energy X-ray absorptiometry. Maximal aerobic capacity (VO_2max ) and time to exhaustion (T_max ) were determined during maximal rowing ergometer testing followed by 1 minute of recovery. HRR was expressed absolutely and as a percentage of maximal HR (HRR%_{1 min} ). Variables were compared using paired Wilcoxon tests. Multivariable regression models were used to predict in-season changes in HRR using changes in VO_2max and T_max , while accounting for changes in BF%. From preseason to post-season, VO_2max and BF% decreased (3.98±0.42 vs 3.78±0.35 L/min, P=.002 and 23.8±3.4 vs 21.3±3.9%, P<.001, respectively), while T_max increased (11.7±1.3 vs 12.6±1.3 min, P=.002), and HRR%_{1 min} increased (11.1±2.7 vs 13.8±3.8, P=.001). In-season changes in VO_2max were not associated with HRR%_{1 min} (P>.05). In-season changes in T_max were related to changes in HRR%_{1 min} (β=-1.67, P=.006). In-season changes in BF% were not related to changes in HRR (P>.05 for all). HRR_{1 min} and HRR%_{1 min} were faster preseason to post-season, although the changes were unrelated to VO_2max . Faster HRR%_{1 min} post-season was inversely related to changes in T_max . This suggests that HRR should not be used as a measure of aerobic capacity in collegiate rowers, but is a promising measure of training status in this population.

Keywords: athletes; body composition; body fat; exercise physiology; heart rate recovery; maximal aerobic capacity; rowing; sports science.