To investigate the high V̇O2max observed occasionally in young men who have no history of training.Methods
V̇O2max, blood volume (BV), maximal stroke volume (SVmax), maximal cardiac output (𝑄̇max), and related measurements (reported as mean ± SEM) were studied in six men (mean age 20.0 ± 0.5 yr) with no history of training, who all had a V̇O2max below 49 mL·kg−1·min−1 (LO group) and six age- and weight-matched men (mean age 19.5 ± 0.5 yr) with no history of training, who all had a V̇O2max above 62.5 mL·kg−1·min−1 (HI group).Results
Compared with the LO group, the HI group had a higher SVmax (149 ± 5 vs 102 ± 5 mL), higher 𝑄̇max (28.9 ± 0.9 vs 20.0 ± 1.0 L·min−1) and higher BV (88.1 ± 3.8 vs 76.7 ± 0.9 mL·kg−1). The BV of four participants in the HI group (mean = 92.3 ± 4.3 mL·kg−1) was substantially higher than the BV of all participants in the LO group, but two participants in the HI group had a BV (mean = 79.7 ± 0.8 mL·kg−1) that was similar to the mean BV of the LO group.Conclusion
The primary explanation for the high V̇O2max observed occasionally in young men who have no history of training is a naturally occurring (perhaps genetically determined) high BV that brings about a high SVmax and 𝑄̇max. However, some young men with no history of training have a high V̇O2max, SVmax, and 𝑄̇max possibly because a greater portion of their BV is hemodynamically active.