To Rest or Not To Rest
Looks like the lion made his choice. What is your choice?
If you’ve been training hard and eating right can you and should you spend some time like the lion above? Certainly.
The training you are engaged in breaks down muscle tissue. During the workout, you are causing micro tears in the muscle tissue. You are also creating a buildup of metabolic waste products. These tears and waste products provide biochemical signals to your body to begin the repair process.
Repairing muscle tissue takes time. This process is called muscle protein synthesis (MPS). Most studies suggest that MPS is elevated about 36 to 48 hours post exercise stimulus. [1-3]
Therefore, resting the muscle fibers you worked 24 hours ago is reasonable because your MPS is still elevated. Meaning you are still benefiting from the work you did yesterday! You can work out the next day. However, your workout should consist of different movements from the previous training session to ensure you are working different muscles or hitting similar muscles but in different plane of movement so as to hit the fibers uniquely.
Are you concerned that you will lose your gains if you take a rest day?
Not to worry, detraining generally doesn’t occur until about 2 weeks.[4] I am not suggesting you take 2 weeks off, I am merely pointing out that your muscle size, strength and endurance will not magically disappear if you take a few days off. There are obviously good reasons to continue to train even though you COULD safely take 2 weeks off without detriment to your muscular improvements. Two of those reasons are 1) exercise's positive impact on mood and 2) the metabolic boost you receive from exercise.
Side note:
Why do you gradually lose my muscle size and strength in the first place?
Muscle is metabolically expense, meaning it requires calories and nutrients to maintain it. If you are not giving your body a reason to maintain the muscle, it will gradually let it atrophy. Your body is constantly in a process of protein turnover. Meaning there is protein synthesis and protein breakdown happening all across your body. In a muscle tissue that is not being trained, it has negligible stimulus for protein synthesis, thus the protein breakdown will outweigh the synthesis and the net result will be less muscle tissue.
If the only factor we looked at were muscle fibers, then 48 hours could be a reasonable amount of time between conducting similar workouts (in which you worked the same muscle in the same way you did 2 days prior). I say, it could be a reasonable amount of time assuming your training is sensible. If you are breaking down your muscles too much by doing excessive training, then there is no way you are recovered after 48 hours. Basically, there is a plateau you reach and doing additional work past that point yields no benefits and only digs you into a hole. [5]
Let’s assume your training is sensible and your muscles are recovered after 48 hours. Are your muscles the only thing to concern yourself with?
No, your tendons, ligaments and central nervous system all need rest and recovery as well. And that is still not all you should concern yourself with. You should be monitoring your mood, motivation, sleep, health (are you getting sick more often?) and perhaps the most overlooked factor (although it should obviously be important), your performance in the gym.
If you find yourself in a bad mood, having little motivation to workout, not sleeping well, catching cold or getting weaker in the gym, does it matter if your muscles are technically recovered? No. Take a day and rest.
If you find yourself with recovered muscles, joints that feel great, no sickness, positive mood, what about then? You are sleeping well and eating great, should you keep training and avoid a rest day? Are there any other factors to consider? Yes, how about time with friends and family? Work, life, and family balance? Hobbies? Remember, this is about long term health and wellness. This is about body and mind. If working out and eating healthy leaves you with no time for family, friends, or hobbies, then you are not fulfilling your potential to be the best possible you.
What about the person who has checked all the boxes above? They feel great, their family life is awesome; do they keep training without a rest day? Maybe, but with a few caveats.
New trainees will make progress very quickly and can likely get away with training daily because they are not yet that strong and are not causing much muscular damage or overall fatigue.
You may be able to train daily provided your workouts are set up in a fashion that works different muscle groups or similar muscle groups but in a different plane of movement and/or rep range.
You may be able to train daily if you remind yourself you are chasing improved performance and not just chasing the stimulus of being sore or tired. Sore and tired is NOT the goal, improvement is the goal.
Active Rest may be a way to be active every day without beating yourself up. Active rest is the idea of engaging in an activity that will not tax you severely but will get the blood flowing.
To Recap:
A rest day or two will not derail your efforts.
Do not let enthusiasm burn you out. Make this a habit you can do long term.
Do not neglect family, friends and mental health.
Try active rest.
I hope this helped how you think about rest!
I will close with a quote from Shakespeare's Macbeth regarding one of the most important parts of your rest and recovery; sleep.
Sleep that knits up the ravell’d sleave of care, The death of each day’s life, sore labour’s bath, Balm of hurt minds, great nature’s second course, Chief nourisher in life’s feast.
Reference:
https://www.ncbi.nlm.nih.gov/pubmed/8563679
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5157116/
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3464665/
http://sci-fit.net/2017/detraining-retraining/#When_do_you_lose_muscle_mass
https://www.ncbi.nlm.nih.gov/pubmed/28729395
