Validity and sensitivity of field tests’ heart-rate recovery assessment in recreational football players

We aimed at examining the criterion validity and sensitivity of heart-rate recovery (HR(Rec)) in profiling cardiorespiratory fitness in male recreational football players in the untrained and trained status, using endurance field-tests. Thirty-two male untrained subjects (age 40 ± 6 years, VO(2max) 41.7 ± 5.7 ml·kg(-1)·min(-1), body mass 82.7 ± 9.8 kg, stature 173.3 ± 7.4 cm) participated in a 12-week (2‒3 sessions per week) recreational football intervention and were tested pre- and post-intervention (i.e. untrained and trained status). The participants performed three intermittent field tests for aerobic performance assessment, namely Yo-Yo intermittent endurance level 1 (YYIE1) and level 2 (YYIE2) tests, and Yo-Yo intermittent recovery level 1 (YYIR1) test. VO(2max) was assessed by performing a progressive maximal treadmill test (TT) and maximal HR (HR(max)) determined as the maximal value across the testing conditions (i.e., Yo-Yo intermittent tests or TT). HR(Rec) was calculated as the difference between Yo-Yo tests’ HR(peak) or HR(max) and HR at 30 s (HR(30)), 60 s (HR(60)) and 120 s (HR(120)) and considered as beats·min(-1) (absolute) and as % of tests’ HR(peak) or HR(max) values. Significant post-intervention improvements (p<0.0001) were shown in VO(2max) (8.6%) and Yo-Yo tests performance (23–35%). Trivial to small (p>0.05) associations were found between VO(2max) and HR(Rec) (r = -0.05−0.27, p>0.05) across the Yo-Yo tests, and training status either expressed as percentage of HR(peak) or HR(max). The results of this study do not support the use of field-test derived HR(Rec) to track cardiorespiratory fitness and training status in adult male recreational football players.