Marathon Runners do not Benefit from Concurrent Strength Training

If you are an avid reader of fitness magazines, you will certainly be familiar with the advice not to neglect strength training, even if your fitness goals are by no means strength-related. While this advice is certainly sound in view of "overall fitness" or weight loss, a recent study by Ferrauti et el. (Ferruti. 2010) found that recreational marathon runners are just wasting their time if they add 2x 120 min weight-lifting sessions to their weekly training regimens.

The initial values for VO2peak (ES: 52.0 ± 6.1 vs. E: 51.1 ± 7.5 ml·kg-1·min-1) and anaerobic threshold (ES: 3.5 ± 0.4 vs. E: 3.4 ± 0.5 m·s-1) were identical in both groups. [...] No significant differences between the groups and no significant interaction (time × intervention) were found for V?o2 (absolute and relative to VO2peak) at defined marathon running velocities (2.4 and 2.8 m·s-1) and submaximal blood lactate thresholds (2.0, 3.0, and 4.0 mmol·L-1). Stride length and stride frequency also remained unchanged.

With an increase in maximal isokinetic leg-strength being the only result of the trainees' gym-efforts, recreational marathon runners would be ill-advised to further weaken their immune system by taxing their bodies on the road and in the gym.