You may start exercising for a lot of different reasons: You need to lose weight for your health. You plan to run a 5K or marathon. You want to enhance your fitness forcross country skiing or to impress at the beach.
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Whateveryour motivation, expect to gain a few poundsat first.But don’t panic. The pounds won’t hang around if you keep at it.
“The key point here is that weight and muscle mass changes will occur,” says physical therapistGary Calabrese, DPT. “Initially, they aren’t all what some people may perceive as headed in a positive direction ― because you may gain a little weight at first.”
Why the initial weight gain?
When you startanexercise program, your body naturally goes throughseveral changes in thefirst couple months.
A newexerciseregimenputsstress on your muscle fibers. This causes small micro tears, also known as micro trauma, and some inflammation. Those two conditions in your muscle fibers are the reason you may gain some weight.
Your body responds to the micro tears and inflammation in two ways that cause temporary water weight gain.
The first is a healing response.
“That stress and micro-tearing damage to the muscle fibers induces water retention in the body,” Dr. Calabrese explains. “There may be a small amount of inflammation around the micro tear, and your body retains fluid there to try to heal it.” These are short lived changes in the muscle.
You will also most likely experience delayed onset muscle sorenessin the 24 to 36 hours after exercising. That is your body’s natural response to those micro muscle tears and the breakdown in muscle tissue.
So, don’t overdo. Eat properly and give your muscles the proper amount of rest so they canheal and rebuild, Dr. Calabrese says.
Increased muscle fuel also adds a little weight
The wayyour body provides energy to the muscles also can add weight at first.
Glycogen or sugar that your muscle cells convert to glucose is the energy source for your muscles. Whenyou exercise regularly, your body stores more glycogen to fuel that exercise.
Stored in water, glycogen has to bind with water as part of the process to fuel the muscle. That water adds a small amount of weight, too.
“As your muscles become more accustomed to the exercise and more efficient, however, they begin to need less glycogen to maintain the same level of energy output,” Dr. Calabrese says. “Thus, your water retention becomes less, so yourweightwill start to go down.”
You will start to lose that initial water weight gain (of roughly one to three pounds) a few weeks or a month after starting an exercise program, he says.
Secondary weight gain from new lean muscle mass
There is another source of weight gainthat people often misunderstand, Dr. Calabrese says.
You will gain weight from lean muscle mass that you add by building your muscles with exercise or weightlifting. But this won’t happen right away.
It will take you at least a month or two to add any lean muscle mass that would show up in your weight. By that point, you will probably be experiencing a good weight-loss trend because of the exercise.
“Again, people may not consider the early changes to their bodies as positive,” Dr. Calabrese says. “But there will be good changes later, so you have to stick with your exercise program.”
Get informed guidance before you start
Before you add any exercise to your routine, talk to your doctor to make sure your body is healthy enough for exercise.
Next, sit down with a medically based physiologist, physical therapist or athletic trainer who is well-versed in the effects of exercise. They can help you map out your exercise program, learn about the proper nutrition and rest you will need, and discuss thechangesyour body will experience as a result of your training.
Then, get on withyour program.
And look forward to the final step — when you take that new body of yours out to enjoy the ski slopes or a sunny, sandy beach.
FAQs
Exercising causes microtears and water retention
Is it normal to gain weight when you first start working out? ›
This causes small micro tears, also known as micro trauma, and some inflammation. Those two conditions in your muscle fibers are the reason you may gain some weight. Your body responds to the micro tears and inflammation in two ways that cause temporary water weight gain.
Why am I gaining weight when I am exercising more? ›
Increased muscle mass
It sounds bad, but it's actually a good thing. After your workout, your body works to repair these tears, allowing your muscles to get bigger and stronger. So even though you may be losing fat, you're gaining muscle. You might feel slimmer, even as the number on the scale rises.
Is it normal to gain weight before losing it? ›
You'd think that going on a strict diet and exercise regimen would help you drop pounds quickly, but most people actually gain weight at first. If this has happened to you, don't give up on your goals just yet.
How long does temporary weight gain after exercise last? ›
Temporary weight gain after exercise can last from two days to 14 days, and there are four main causes of this weight gain. The first cause is soreness, which is the body repairing itself after the workout. Foam rolling can help avoid this weight gain.
Why am I gaining weight while working out and in a calorie deficit? ›
Decreased Muscle Mass
Your body composition may be another reason why you are still gaining weight while in a calorie deficit. If you have a higher body fat percentage and lower muscle mass, then you are probably burning fewer calories than if you had more muscle mass.
Why is my stomach getting bigger with exercise and diet? ›
Different factors, such as a sedentary lifestyle, hormones, and the foods you eat may increase your abdominal fat. This can include not consuming too much sugar and not enough fiber and protein. Getting rid of excess belly fat, or abdominal fat, is a common goal for many.
Why am I gaining fat instead of losing when working out? ›
Sweating during a workout can cause us to temporarily retain water, which can make us feel bloated and cause the scale to look higher than it did yesterday. Also, you may be losing fat, but you're also building muscle at the same time, which can cause the scale to stay the same or even increase.
How long does it take to start losing weight when exercising? ›
The answer depends on your goals—whether you are improving your cardio, gaining muscle, or losing weight—and your fitness level. For example, people who are new to working out will typically see cardio and muscle gain within two to four weeks. In contrast, significant fat loss might take around four months or longer.
Why is my belly fat increasing even after exercise? ›
There are many reasons why people gain belly fat, including poor diet, lack of exercise, and stress. Improving nutrition, increasing activity, and making other lifestyle changes can help people lose belly fat.
You May Be Retaining Water. Since the human body is mostly comprised of water, it's only logical that our bodies will hold on to excess amounts of water from time to time.
Why am I walking more but gaining weight? ›
Improper lifestyle habits can lead you to gain weight even after you start walking. For example, unhealthy sleeping habits, improper diet, intake of too many calories and excessive stress and anxiety problems often are the main reasons why individuals keep gaining weight even after they start walking.
Can too much cardio cause weight gain? ›
According to Noah Abbott, a CrossFit coach in Brooklyn, prolonged, steady-rate cardio can deplete our body's Triiodothyronine, or T3 hormone. This hormone is responsible for metabolism, and a depletion of this hormone can cause the body to go into a mode where it stores and gains more fat than usual.
Why am I gaining weight when I just started working out? ›
Gaining weight after working out is likely due to muscle fiber inflammation, muscle glycogen and water weight gain, and over time, muscle mass gain. If weight loss is your goal, seeing an increase on the scale when you've been making an effort to exercise can be frustrating.
Why am I gaining fat after working out for 3 weeks? ›
Muscle weight gain is obviously a good thing, but your body will respond to this inflammation by temporarily retaining water, which can lead to increased water weight. And that's OK! Let your body heal. Drink plenty of water, eat well, keep an eye on your sodium intake, and get enough sleep.
Why is my body fat increasing with exercise? ›
Tweaking your diet and ramping up physical activity will help you lose weight and build lean muscle mass. You might lose weight but see an increase in body fat percentage because your diet changes and exercise routine might be causing you to store more fat, lose water and burn sugar (glycogen stores), not body fat.
Is it hard to lose weight when you first start working out? ›
It is incredibly common for the scale not to budge for a few days (or weeks) at a time. This doesn't mean that you are not losing fat. You can gain muscle and lose fat at the same time, particularly if you have recently started exercising and are eating a high-protein diet ( 1 , 2 ).
How long does it take for body to get toned? ›
You will need at least four to eight weeks to notice toned muscles. For this, you will also need to follow the right strategy and do exercises for toned body. Your sex, diet, and metabolism also play a vital role in your progress.
Does working out before a weigh in make you heavier? ›
You'll usually weigh less after strenuous physical activity because of the water you've lost through sweating. This is why one of the best times to weigh yourself is in the morning before you've eaten or exercised.
