Not fully recovered - but training again?
Two days after a murderously heavy workout your muscles still feel like they're on fire. You haven't recovered, but nevertheless you train again. Not a good idea according to Finnish sports scientists. They published their conclusions in the Scandinavian Journal of Medicine and Science in Sports. Not letting your body recover disrupts its hormonal response to training.
The Finns got 8 active men [average age 31] to train in a way they were not used to: on a leg-extension machine they did 4 sets to failure with 40 percent of their 1RM. [E1] Immediately after the session the researchers measured the men's levels of adrenalin, noradrenalin, testosterone, cortisol and growth hormone. The concentration of all these hormones should rise after a strength training session.
Two days later, when the men still had sore muscles and had not recovered from the previous session, the Finns repeated the procedure. [E2]
The figure below shows that the men were less strong during E2.
NE = noradrenalin, EPI = adrenalin, COR = cortisol, GH = growth hormone. The production of all of these hormones was lower after E2.
For the production of testosterone it didn't make so much difference that the men had not fully recovered, but for the production of the other hormones that were measured it did make a difference. The production of growth hormone decreased by the most. The production after E2 was 45 percent less than after E1.
Definitely not good for hypertrophy.
Scand J Med Sci Sports. 2011 Dec;21(6):e184-94.
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