WHY SOME PLAYERS IMPROVE A LOT AND OTHERS NOT?

Looking at the data from the 2 studies on elite players mentioned in my articles this week, it is worth noting that there is a large variation in the size of improvement after training.

Let me remind you that in the study with the elite champions league players (probably from FC Barcelona) aerobic fitness, strength and explosiveness were evaluated after the 8-week pre-season training period (Helgerud et al., 2011). Maximal oxygen uptake improved by 8.6% whereas half-squat maximal strength by 51.7%. If one looks more closely to the data

• Maximal oxygen uptake improved by 3-5% in 3 players and 15% in 1 player. Interestingly, the player with 15% improvement had already a high initial value (64 ml/kg/min)
• In maximal strength test, there were players that improved by only 10% and 1 player that improved by 2.5-fold.

In the study with elite players from Italian Serie A (Castagna et al., 2011) time devoted in high intensity training ranged from 120-205 min per week. However, improvements in aerobic fitness ranged from 0 (!) to almost 20%. Another observation: for the same time spend at high intensity training (160 min) 1 player improved by 4%, 1 players improved by 7%, another 1 by 9% and the last one presented NO IMPROVEMENT AT ALL!

It seems, therefore, that

1. Players respond differently with the same training load
2. This happens even at the elite level

The explanation for these results is not clear. Age, initial fitness level and genes (and other, not discovered yet factors) may interact to affect training adaptations.

Whatever the reason, these results highlight the importance of the individualized programs to improve certain aspects of fitness.