What We Lose During a Workout (And How to Replenish It!)

After a grueling workout session, remember to restore these five things to stay healthy and build muscle.

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Exercise, in general, has a host of positive benefits. From increased physical performance, promoting mental clarity, and the ability to reach weight-loss goals! All-in-all, working out can make us feel pretty good-- especially when we know it’s burning extra calories! With that said, calories aren’t the only thing we burn off or sweat out in our workouts; the body releases some pretty vital nutrients such as electrolytes, minerals, and water, as well as the tearing down of muscle fibers! And to keep our workouts strong and results coming, what we lose in our workouts must be replenished properly. So, if you’re looking to maximize the benefits that come from exercise, fitness writer and nutritionist SJ McShane has the top five important depletions we experience during a workout and how to replenish and repair them.

1. Electrolytes

Electrolytes are chemicals that form ions in body fluids such as potassium, sodium, magnesium, and calcium. In short, they help make sure specific bodily functions run at optimal levels such as heart rhythm, regulating blood volume, and maintaining proper muscle and nerve functions. When the body is depleted of these electrolytes, symptoms such as dizziness, heart palpitations, confusion, muscle twitching, and nausea can occur.  During workouts, electrolytes get deposited into sweat glands. Water then follows the electrolytes, and as the glands fill up, they release the salty mix onto your skin. Now depending on the length of your workout as well as intensity and temperature in which you train in, all determine if you need to replenish and how much. Not all workouts call for a sports drink. In fact, 1.5 hours to three hours is long enough to warrant fluid replacement due to sweat losses," says Kristine Clark, Ph., FACSM, director of sports nutrition for Penn State University Park. "How much sweat is lost influences how much sodium and potassium are lost."

2. Water

Something we can’t live without! In fact, research shows that water is the most abundant constituent of the human body totaling about 70 percent of body weight in the normal adult. With that said, it’s the first thing we lose when we work out and the first thing that needs replacing.  In workouts, an average person sweats between 0.8 to 1.4 liters (roughly 27.4 to 47.3 oz.) per hour during exercise.  So how much water do you need for exercise? Amanda Carlson, director of performance nutrition for Athletes’ Performance states: “One to two hours before your workout, drink 15 to 20 ounces of water. 15 minutes before you begin, drink between 8 and 10 ounces of water. During your workout, drink another 8 ounces every 15 minutes. Carlson also recommends that you weigh yourself before and after any type of exercise. “For every pound lost, replace it with 16 to 20 ounces of fluid,” she suggests. If you lose weight during the workout, drink a bit more next time. If dehydration sets in, symptoms such as diarrhea and vomiting, amongst other symptoms can set in. As far as the recommended daily fluid intake: women are recommended to drink around 11 glasses of water or 2.2 liters, and for men, it’s about 13 glasses or 3 liters without exercise.

3. Muscle Fibers

Exercising can place a lot of stress on our muscles, and in turn, cause them to develop very small microscopic tears while avoiding injury. This is where soreness can be expected. (Ouch!) The good news is, the healing process begins directly after you work out! The body starts to repair or replace damaged muscle fibers through a cellular process where it fuses muscle fibers together to form new muscle protein strands. To help the muscles recover faster, and to shorten the amount of time in soreness, sleep is one of the most important things you can do for your body- (along with healthy eating). For optimum recovery, 8 hours of sleep per night is recommended. This way the body will accumulate 1.5 to 2.5 hours of REM sleep, which is encouraged for a full recovery. Case in point, catching some good Z’s on a regular basis will make you stronger, fitter and healthier! Also, eating a “complete protein” that contains BCAA’s or branch chain amino acids will ensure that the protein your consuming can be absorbed optimally.

4. Minerals

Just as the body sweats out electrolytes and water, it also expels important vitamins and minerals such as Vitamin C, B6, Riboflavin and Thiamine. Minerals and vitamins such as these play a key role in muscle strength and flexibility, bone density, and heart and lung health. With that said it’s of utter importance to replace these much-needed minerals on the regular! A great way to ensure mineral recovery is with a post-workout smoothie that consists of a mix of fruits such as berries and bananas, nut-milk and a lean protein such as protein powder; consume this or something similar within 30 minutes post-training for optimum absorbency.

5. Calories

Depending on your goals, weight gain is only associated with calorie intake being greater than calories burned. With that said, after certain workouts such as vigorous physical activity, you should have a healthy snack or meal within 15 minutes to an hour post-workout, according to the Academy of Nutrition and Dietetics. Doing so will ensure steady energy throughout the day, and the replacement minerals, vitamins, and calories needed. Some examples of healthy refueling could be chicken, rice, and avocados to a post-workout smoothie. Pairing up good carbohydrates, good fats, and lean protein will help provide your body with the best balance of nutrients it can get! Proper fuel leads to better workouts and that will lead to a leaner body composition. 

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