Estimation of maximal oxygen uptake using the heart rate ratio method in male recreational football players.

Maximal oxygen uptake (VO 2max ) is associated with cardiovascular and metabolic health in the general population. The heart rate (HR) ratio method (HR ratio ) is a valid, easy and accessible method for estimating VO 2max in well-trained subjects. This study examined the validity of using the HR ratio to estimate VO 2max in recreational football players in the untrained and trained states. Sixty-six participants (age 39.3 ± 5.8 years) were tested pre-training and 28 after 12 weeks, for VO 2max assessment, running on a treadmill alternating speed (1 km h -1 ) and inclination (1%) increments every 30 s until exhaustion. Maximal HR (HR max ) was assessed directly with a multiple approach and estimated with selected equations. Resting HR (HR rest ) was measured in supine position, after 15 min of rest. The HR ratio method considers the product of HR max /HR rest ratio by a theoretical proportionality factor (15 ml kg -1  min -1 , TPF) to estimate VO 2max . This population-specific proportionality factor (SPF) was 14.6 ± 2.6 ml kg -1  min -1 . In the untrained state (n = 66), participants' actual VO 2max (41.3 ± 6.2 ml kg -1  min -1 ) was moderately lower (~ 2 ml kg -1  min -1 ) than the estimated VO 2max using the TPF. A nonsignificant difference (0.7 ml kg -1  min -1 ) was found when the VO 2max was estimated using the SPF. When using HR max equations and the TPF, a small nonsignificant difference (~ 1.5 ml kg -1  min -1 ) was reported between actual and estimated VO 2max . In the trained state (n = 28), the estimated VO 2max values were not significantly different from the actual VO 2max (44.2 ± 5.2 ml kg -1 min -1 ), with large effect sizes when considering TPF and estimated HR max . The results of this study provide evidence of the applicability of HR ratio in estimating VO 2max in male adult/middle-aged recreational football players.