Use it or lose it:

The focus of this blog piece will be around quantifying the rate of decline in muscle mass resulting from the effects of disuse and time off from the gym. Whilst not intending to be a fear mongering post, I do feel it is important that you understand how rapidly the body can change for the worst during a period of time off. Not only can the body decrease muscle protein synthesis, it can also become more resistant to building lean tissue which over all makes it harder to gain back any muscle lost in the first place.

The facts:

Wall et al. (2016) hypothesize that short term periods of immobilisation leading to disuse of skeletal muscle enhances the rate of sarcopenia over a person’s life span. The research group assessed the quadriceps cross sectional area as well as the postabsorptive myofibrillar protein synthesis rates following a period of 5 days of immobility of the subjects leg (Wall et al., 2016). The findings of this study were that after just 5 days, the leg cross sectional area was down 3.9 ± 0.6% and the post absorptive myofibrillar protein synthesis rates were down 41 ± 13%. The researchers were able to conclude that just 5 days of disuse was enough to substantially lower protein synthesis rates and lead to muscle atrophy in disused limbs (Wall et al., 2016). Wall, Morton and van Loon (2015) suggest that whilst the rate of decline is substantial, keeping quality protein ingestion high within the diet is a great way to try and offset the decline in muscle cross sectional area. This is especially important for athletes who are over coming injury or those on a period of hiatus from their regular strength training routine (Wall, Morton & van Loon, 2015).

How to offset the loss:

There are really only two possible ways to reduce the rate of muscular atrophy within the body. Number one being highlighted by Wall, Morton and van Loon (2015), who suggest being mindful of protein intake, timing and quality throughout your day. Option two being supported by Hume, Cheung, Maxwell and Weerapong (2004), who propose the repeated bout effect of resistance training. The authors suggest that a bout of resistance training at least one time per week provides the stimulus necessary for an increase in muscle protein synthesis and to offset the rate of muscle protein degradation (Hume, Cheung, Maxwell & Weerapong, 2004). The authors also highlight a single bout of resistance training as being enough stimuli to protect the body from the severity of delayed onset muscle soreness for the next bout of training. This is something I alluded to within my hypertrophy specific mini-series.

My thoughts on the matter:

For me, I see building muscle tissue within the body as an uphill battle at the best of times. There are many factors which are at play within the body to either build us up or tear us down and unfortunately, time away from the gym is the biggest player in increasing muscle turnover or degradation. There are neurological and physiological adaptations which happen within the body in the beginning stages of a resistance training program which tend to slow down over time, as the rate of return on investment declines. This is not to deter somebody from continually striving for more within the gym, but it is to be realistic and say that we will not always improve as fast as we once did. With this in mind, we must highlight however, that the rate of decline is the same no matter how trained or untrained we are. What a trained body has though, is a higher starting point to mitigate the losses seen with de-training or time off from exercise. The ceiling limit is higher in the well trained person and they will take longer to end up back at square one than the beginner, however the rate of decline is the same. We all fall down at the same rate which is why it is important to understand how to offset the loss, even if it is inevitable that there will be a loss. As highlighted throughout this post, having good quality protein ingestion is a good defence against muscle atrophy. Second to this, is trying to get in at least one training session per week. This does not have to be from a specific gym work out, and can be from an exercise stimulus you are not accustomed to such as hiking, swimming or body weight exercises. If on holiday or injured, something is still better than nothing.

References:

Hume, P.A., Cheung, K., Maxwell, L., & Weerapong, P. (2004). DOMS: an overview of treatment strategies. International SportMed Journal, 5(2), 98-118.  

Wall, B.T., Dirks, M.L., Snijders, T., van Dijk, J.W., Fritsch, M., Verdijk, L.B., & van Loon, L.J.C. (2016). Short-term muscle disuse lowers myofibrillar protein synthesis rates and induces anabolic resistance to protein ingestion. American Journal of Physiology, 310(2), 137.  

Wall, B.T., Morton, J.P., & van Loon, L.J.C. (2015). Strategies to maintain skeletal muscle mass in the injured athlete: nutritional considerations and exercise mimetics. European Journal of Sports Science, 15(1), 53-62.