Abstract 13468: Left Ventricular Mass Increases with Life-long Training Volume Irrespective of Scaling Unit.
Purpose: Previous findings suggest that left ventricular mass (LVM) indexed to levels of Fat-Free Mass (FFM) are not different in endurance trained individuals compared to non-trained controls suggesting that the physiological cardiac hypertrophy in athletes is a response to increased levels of FFM. To date, no studies have investigated whether there is a dose-response of LVM to training volume (number of training sessions/wk) over a life-time, and whether the LVM-FFM relationship is consistent across all training levels.
Hypothesis: LV mass will increase with training volume, and differences in LVM between Masters Athletes and untrained controls will not be reduced when indexed to FFM.
Methods: Maximal oxygen uptake (VO2max), LV mass and end-diastolic volume (MRI) and body composition (underwater weighting) were collected in 87 healthy trained and untrained older (>60 years) individuals. These included 25 untrained subjects who had consistently (>20 years) performed <2 sessions/wk (Q1), 14 subjects who performed 2–3 sessions/wk (Q2), 23 subjects who performed 4–5 sessions/wk (Q3) and 25 Maters Athletes who performed 6 or more sessions/wk plus regular competitors (Q4).
Results: In all subjects, LV mass correlated with VO2max (ml/kg/min) (r= 0.55, p< 0.001). BSA (r= 0.59), height (r= 0.68), weight (r= 0.52) and FFM (r= 0.68) were correlated with LV mass (all p< 0.001). LV mass was greater in the groups with the highest training volume (Q3 and Q4) compared to the group with the lowest training volume (p= 0004 and p= 0.022 respectively) (Table 1). These differences remained regardless of whether LVM was indexed to BSA, height or FFM.
Conclusion: LV mass increased with life-long training volume, and remained larger in groups with the highest training volume irrespective of scaling unit. These findings suggest that FFM is not primarily responsible for the larger LVM as assessed by MRI in older adults who have performed >3 sessions/wk during their adult lives.
- © 2010 by American Heart Association, Inc.