Hard work is supposed to get you results, but if you work too hard, it can be counterproductive. That's one of the great conundrums of exercise. It's a balancing act to figure out how often you can work out and how often you should rest. The answer depends on a few things like experience level and diet, but your muscles generally need 24 hours of recovery time after a workout.
Muscle Damage From Workouts
To put it simply, workouts tear you down and your body has to build itself back up. While it might sound dramatic, workouts are damaging to your body. When you lift weights, your muscles suffer extremely small tears that you need to recover from. It's nothing to be afraid of, because you come back stronger than before as long as you take time to recover.
Protein Repairs Muscle
After a workout, your body goes into repair mode. It starts to create protein from amino acids in your bloodstream. These amino acids are molded into new muscle tissue, which your body lays down to replace older, more damaged muscle. This process of regeneration occurs very slowly unless you have something to kick-start it, like a workout.
Muscle Inflammation From Workouts
To recover, your muscles need more blood. That's how your body sends nutrients to damaged tissue. This process is also known as inflammation. While it can be painful and is perceived as a bad thing, inflammation is necessary for recovery after a workout.
Around 24 to 48 hours after a workout, your muscles reach the peak of their inflammation and begin to taper off, according to a 2017 research review published in the Journal of Applied Physiology. That's why you don't want to hit the same muscles within a 24-hour period. They need time to recover and rebuild.
Eccentric Vs. Concentric Exercise
When you lift a weight, there's an eccentric and concentric portion of the exercise. The concentric portion is when you lift the weight. If you're doing a bicep curl, that's when the weight comes up toward your shoulder. The eccentric portion is when you lower the weight back down.
Each portion of the lift has unique benefits to the muscle. They're also equally important in terms of muscle growth, according to a 2017 study published in Frontiers in Physiology. The big difference between the two is that the eccentric portion is more damaging to your muscles.
Some people like to accentuate the eccentric portion of an exercise, which helps with muscle growth, but it's important to keep in mind that this style of training is more damaging than doing an exercise at a normal speed.
Isolating a muscle makes it work harder, which increases your recovery time. Single-joint exercises isolate muscles more than multi-joint exercises. A bicep curl, for example, isolates your biceps. The only thing moving is your elbow, which means that your biceps is doing all the work.
A chin-up is a multi-joint exercise that works big back muscles like the lats, but the smaller bicep muscles contribute to the movement. Your shoulder and elbow joint have to work to pull your body up. Since there are other muscles and joints involved in the movement, your biceps aren't taking the brunt of the load.
Monitor Your Workout Volume
The volume you do in one workout affects recovery time. Volume is the product of the weight you use multiplied by the number of sets and reps you do. To put it simply, the more you do in your workout, the longer it takes to recover. However, as your body adapts to workouts, recovery time decreases once again.
Rest Between Workouts
As you progress, that might not be enough to tax your muscles. To make your exercise program more intense, you might need to add days. To do this, you'll need to split up body parts so that you don't work the same thing two days in a row.
For example, you can work the upper body on one day and the lower body the next. Alternating between these two leaves 48 hours in between workouts for each muscle group. You also get to focus more energy on fewer body parts.
Keep in mind that a split workout routine is for more advanced trainees and might not be necessary for you.
Nutrition Affects Recovery
The amount of time it takes for you to recover depends on your nutrition as well. What you eat during and after your workout can shorten or lengthen your recovery time. Muscle is made of amino acids, which you can get from the protein you eat or supplements you take.
Out of the 20 amino acids, three of them are particularly important for muscle building. They're called branched-chain amino acids (BCAA). Leucine, isoleucine and valine are the proper names of the three BCAAs, according to a 2017 study published in the Journal of the International Society of Sports Nutrition. Your body can't produce them, so you have to get them from food.
Supplements for Recovery
A 2017 study published in Applied Physiology, Nutrition and Metabolism shows that BCAA supplementation reduces your recovery time. In the study, the researchers found that strength rebounded faster and subjects weren't as sore the day after taking BCAAs.
Whey protein naturally contains BCAAs, making it a suitable replacement. You can also simply focus on eating more protein throughout the day from animal or plant sources. It will help your muscles recover faster.
If you don't let your muscles properly recover, it can hurt your performance in the gym and potentially cause injury. A 2016 study published in the Journal of Strength and Conditioning Research showed that training without allowing your muscles 24 hours to recover hurt performance and results from training.
What Works for You?
The key is to find what's best for you. If you were to create a graph showing how your muscles respond, it would look like an inverted "U." It's also known as a bell curve because it looks like a bell. If you don't work out, you don't get results and the graph is flat. For each day you add to your workout routine, the results go up.
There's an optimal point where you hit your perfect number of workouts, which is the peak of the graph, then everything goes downhill again once you go past that. The top point is different for everyone, so experiment with more or fewer workouts during the week to see what feels best for your body.
- Journal of Applied Physiology: Muscle Damage and Inflammation During Recovery From Exercise
- Sports Rec: What Are the ACSM Guidelines for Strength Training?
- Applied Physiology, Nutrition and Metabolism: The Effects of Acute Branched-Chain Amino Acid Supplementation on Recovery From a Single Bout of Hypertrophy Exercise in Resistance-Trained Athletes
- Frontiers in Nutrition: Effects of Protein Supplementation on Performance and Recovery in Resistance and Endurance Training
- Journal of Strength and Conditioning Research: Specific Training Effects of Concurrent Aerobic and Strength Exercises Depend on Recovery Duration
- Frontiers in Physiology: Skeletal Muscle Remodeling in Response to Eccentric vs. Concentric Loading: Morphological, Molecular, and Metabolic Adaptations
- Journal of the International Society of Sports Nutrition: Branched-Chain Amino Acids and Muscle Protein Synthesis in Humans: Myth or Reality?
- ACSM: Resistance Training for Health and Fitness