How to Rest for Body Recomposition

Rest days are the recovery periods between training sessions when the physiological processes that build muscle and adapt to exercise occur. 

This article explains the role of rest and recovery in body recomposition and how they support muscle repair and long-term progress. Even if training and nutrition are optimised, most of the actual changes occur during the recovery period, not during the training session itself. 

Resistance training doesn't build muscle directly — it damages and disrupts muscle tissue whilst triggering signals for adaptation.

The actual construction of new muscle protein occurs during the hours and days following training, when your body is resting. So, insufficient rest and recovery between training sessions can hamper the adaptive response to training, your performance (and thus muscle growth)¹.

For body recomposition, recovery is particularly important as you're attempting to build muscle in a suboptimal environment (because you are energy-restricted). So, maximising the quality and efficiency of recovery periods becomes even more important when energy is limited.

Does Sleep Help Muscle Growth?

Sleep represents the longest uninterrupted recovery period of your day. There is no other opportunity where you get 6–8 hours of complete and consecutive rest.

Research consistently demonstrates that good sleep is important for muscle growth². During sleep, particularly deep sleep, growth hormone peaks, creating a hormonal environment that favours growth. 

Multiple studies have shown that protein consumed before sleep is effectively digested and absorbed, and can stimulate muscle growth processes throughout the night³. Sleep deprivation impairs muscle growth processes, even when you’re training and consuming enough protein⁴.

It appears that sleep deprivation alters some of your hormones (like testosterone, cortisol and insulin-like growth factor 1) — which shifts your body towards breaking down muscle, rather than growing it.

Practically, this means that sleep restriction, which means consistently having less than seven hours per night, will impair body recomposition efforts. So, sleep quality and duration should be considered alongside training and nutrition.

Does Sleep Help with Fat Loss?

Another “double-effect”. In addition to blunting muscle growth, sleep can also derail fat loss. 

Sleep restriction alters your appetite hormones, making you hungrier and more likely to adhere to calorie-restricted diets⁵. Even just a single night of bad sleep can increase hunger. Over multiple days, these effects can compound, creating a drive to consume more food. 

This effect isn't trivial — persistent poor sleep has been shown to increase daily calorie intake by roughly 200–500 kcal through hunger alone⁶

More bad news. Sleep deprivation appears to increase preferences for calorie-dense fatty, sugary and salty foods. This isn’t a failure of willpower; it's how your brain responds to food cues. 

Poor sleep also has a second, independent effect on energy balance: it reduces how much you move. Sleep-deprived people tend to show lower non-exercise activity — walking less, fidgeting less — alongside reduced exercise performance, which can add up to a few hundred fewer calories burned per day.

Much of this happens below conscious awareness, so you may not notice your activity level dropping. Poor sleep also appears to impair how efficiently your cells use fuel, blunting insulin sensitivity in a way that favours storing energy as fat rather than burning it.

For body recomposition, which requires maintaining a moderate energy deficit consistently over weeks or months, poor sleep creates a dual problem: it simultaneously impairs the muscle-growth response to training and makes your diet more difficult to follow. Both effects undermine the goal of improving your body composition.

Practically, prioritising seven to nine hours of quality sleep per night is essential. This includes not just total sleep duration but also sleep consistency (regular bedtimes and wake times) and sleep quality (minimising interruptions). Treating sleep as a negotiable variable or something to sacrifice will be counterproductive to body recomposition goals.

Sleep

Sleep is your body’s essential recovery period. It’s when your brain clears waste, your heart rests, your hormones and your brain reset themselves.

Alphabet Guides

Stress, Hormones and Energy

Stress, be it psychological or physical, can also affect body recomposition, as it stimulates the release of certain hormones, like cortisol⁷. Cortisol affects muscle in a few different ways. 

1. It increases muscle breakdown while also suppressing growth processes. 
2. It blunts the effects of another hormone, insulin, which helps support muscle growth. Even with adequate protein intake, chronically elevated cortisol can impair muscle growth. 
3. Another double-effect, cortisol influences 'energy partitioning', increasing fat storage, particularly visceral fat, while blunting muscle growth. 

This is thought to happen as cortisol acts as a signal that (because of stress) energy needs to be conserved (to deal with the stress), and muscle is a nonessential luxury. While this might be a perfectly healthy evolutionary response to stress, it will directly undermine body recomposition efforts.

Cortisol also drives cravings for calorie-dense, palatable foods specifically⁸, which compounds its direct effects on fat storage — it's not just changing where energy goes, but how much you're inclined to eat in the first place.

In addition to everyday psychological stressors (like work, relationships, and financial worries), specific recomposition requirements like muscle soreness from training, hunger from energy deficits, and planning to meet nutritional targets can add extra stress. So you’re best keeping all forms of stress to a minimum.

It's worth being honest about the limits of the evidence here: no specific stress-management technique has been directly shown to improve muscle growth — only exercise itself has that evidence behind it. Managing stress well may still indirectly support training performance and recovery, which is reason enough to prioritise it.

The Stress–Sleep Doom Loop

Poor sleep and chronic stress don't just act in parallel — they tend to make each other worse. Poor sleep and stress contribute to weight gain, which can bring on problems like sleep apnoea or low-level inflammation-driven discomfort. Those, in turn, disrupt sleep and elevate stress further, which drives further weight gain — and the cycle continues⁹.

But the encouraging part is that this works in reverse, too.

Quality sleep and effective stress management don't just avoid the downward spiral — they actively amplify the benefits of your training and nutrition efforts. And unlike diet or training changes, which typically take weeks or months to show results, the mood, behavioural, and metabolic benefits of better rest tend to show up within days¹⁰.

Stress, Recovery and Recomposition

When training stress exceeds your ability to recover, your performance will decline, and the adaptive response to training will be impaired.

“Overtraining” or “Under-Recovery” manifests itself in a few ways: muscle soreness, weakness, mood changes, poor sleep or increased susceptibility to illness. One or more of these symptoms typically indicate that something isn’t working quite right under the hood. 

Poor recovery may not just pause, slow or impair progress — it may actually reverse it¹¹. The practical implication is clear: more training is not always better, especially if you’re on an energy-restricted diet.

There is an optimal dose of training stimulus that maximises adaptation without exceeding recovery capacity. Exceeding this dose, even with the best intentions, may undermine results.

Structuring Rest Around Training

During training

Recovery isn't just about days off — it also happens in the seconds and minutes within a session. Rest periods between sets sit at the centre of an ongoing debate: shorter rests (under 60 seconds) favour metabolic stress and hormonal responses, while longer rests (over two minutes) let you lift more weight and generate more mechanical tension — generally considered the more important driver of growth.

The evidence is mixed on which wins out overall, so resting 1–3 minutes between sets is a sensible default; beyond that range, other training variables likely matter more^12,13.

Between training sessions

Between sessions, the standard minimum is around 48 hours of recovery per muscle group, though unfamiliar, high-intensity, or compound (multi-joint) exercise can require longer.

You don't have to take 48 hours off training altogether — splitting sessions across different muscle groups lets you train more frequently while still respecting this window. Good muscle growth is achievable on as few as 2–3 non-consecutive sessions per week per muscle group, though more frequent training with shorter between-session gaps generally produces better results.

How much recovery you personally need varies with training experience, age, nutrition, sleep, lifestyle, and genetics, so treat any fixed number as a starting point rather than a rule¹⁴.

Consistency Beats Intensity

Body recomposition is inherently a moderate, sustained process rather than a rapid, magical transformation. The limited availability of energy, extra stress and some hormonal changes favour consistency and moderation over crash diets and German volume training.

The person who achieves perfect adherence for two weeks before giving up will be worse off than the person who hits their targets 80% of the time but keeps it going for three months.

Because many of these things that we’ve discussed interact with each other, you cannot optimise one thing (e.g., strength training) while ignoring other things (sleep, nutrition, recovery, etc).

It is also extremely difficult to offset one thing by increasing the other: for example, increasing the amount of training you are doing to counteract a bad diet.

Active Recovery on Rest Days

Complete rest has its place, but low-intensity movement on non-training days tends to speed recovery more effectively than doing nothing at all. Walking, easy cycling, swimming, and yoga all improve blood flow, help clear metabolic waste, and maintain mobility.

The key is keeping intensity genuinely low — a reasonable rule of thumb is to finish the session feeling no more tired than when you started.

Other recovery methods (e.g., massage, cold-water immersion, sauna or heat therapy, contrast hydrotherapy, and compression garments) have reasonable evidence behind them too, but tend to be less effective, and less cost-effective, than simply moving¹⁵.

Practical considerations