…a popular practice where guys essentially take some time off of hard training. Some people still go to the gym, and work on things like flexibility, mobility, and just hit some light weights to get a nice pump. Others just literally take 5 or more days off from the gym and worry little about muscle loss or fat gain. One of these is the wrong way to do things…
The Myostatin De-mobilization Study
A new study wanted to find out just how much muscle a person can lose in 5 days as a result of de-mobilization. It intent was to mimic an injury where you might be stuck in bed or on the couch for 5 to 14 days in order to properly heal. Now a deload is different then 100% de-mobilization, but this gives us an idea as to how much muscle a person can lose by taking a lazy 5 to 14 days off.
In this case they tested body composition, muscle cross sectional area (CSA – size), myostatin levels, PGC1-alpha levels, strength (via leg extension), and various other factors in young men. Then they put one group in a full leg cast for 5 days, and another group in a full leg cast for 14 days. Being a participant in this study would suck!
Rapid Muscle and Strength Loss
One might not think you could lose a lot of muscle and strength in just 5 days, but maybe in 14 days? Here’s what they found (also refer to charts):
Quad Cross Sectional Area
- Decreased 3.5% after 5 days
- Decreased 8.4% after 14 days
Leg Lean Mass (via DEXA)
- Decreased 1.4% after 5 days
- Decreased 3.1% after 14 days
Leg Extension Strength
- Declined 9% after 5 days
- Declined 22.9% after 14 days
Type II Muscle Fiber
- Decreased insignificantly in the 5 day group
- Decreased 13.4% after 14 days
Type I Muscle Fiber vs. Type II
- Type I increased 10% vs. Type II
- Type I increased 26% vs. Type II
Without going into other factors such as myostatin, and PGC1-alpha, you can already see de-mobilization had a huge impact on muscle loss.
Does this mean a deload is a bad idea?
Yes and no. As I mentioned at the start of this article it’s important to have an active deload. Stretch, work on mobility, keep the muscle active but under less intensity. This will ensure better recovery, and may actually potentiate the growth response once you go back to training intensely. Taking 5 days off and sitting your ass on the couch for a March Madness tournament is going to work against you. Also keep in mind these guys were un-trained (for at least 6 months), so more likely than not, if you were truly training intensely and pushing hard your deload is going to act quite differently on your body than true immobilization.