Exercise and Weight Loss: Does Activity Enhance Your Efforts?

Exercise and weight loss continue to be hot topics! Recent research has found that 42% of people are currently trying to lose weight, and exercise is the most common strategy—65% of those trying to shed pounds rely on physical activity. 

It is incredibly frustrating to begin a new habit and not see the results of all of your hard work. Most of us know the pain of stepping on that dreaded scale with hopeful anticipation, only to be greeted by a flashing number that is not what we had been envisioning.

No Shortage of Reasons to Exercise in the Long-Term

To be sure, there are dozens of reasons to prioritize physical activity in your daily life. If you want to reduce your risk of the diseases that plague modern Americans, including heart disease, diabetes, osteoporosis, and some forms of cancer (among them, colon, breast, uterine, and lung), exercise is an excellent habit to pick up. Sometimes, though, as I’ve discussed in previous posts, it’s hard to do challenging things and to leave our comfort zones for the goal of maybe preventing disease in the future. 

Plenty of Immediate Exercise Benefits, Too

Most people respond better to immediate results and rewards for their effort. If that sounds like you, keep in mind that exercise’s mental and emotional benefits are instantaneous. The relaxation-promoting chemicals released during physical activity help us to manage stress and reduce the risk of depression. Exercise can also help you function better in daily life by enhancing your ability to learn new tasks and sharpening your judgment skills. If sleep is a problem for you, like it is for up to 70% of Americans at least once per month, exercise can also help you fall asleep more quickly and stay asleep longer. 

Exercise and Weight Loss

All that being said, the research on exercise and weight loss can be disappointing to many people. Physical activity triggers hormonal changes that increase appetite; if we are not very careful, it is frightfully easy to out-eat all of the work that we put in at the gym. The hard truth is that your body doesn’t like to lose weight; it goes against survival instincts that have biologically prepared us for tough times ahead. 

Calories Burnt (based on a person weighing approximately 200 pounds)Calories Consumed
Sitting still – 130 calories in an hour1 large banana – 121 calories
Walking slowly – 255 calories in an hourCrunchy peanut butter Clif bar – 260 calories
Canoeing – 319 calories in an hour1 cup Raisin Bran cereal and 1 cup 2% milk – 320 calories
Downhill skiing – 391 calories in an hour2 ounces cheddar cheese and 10 crackers – 388 calories
Low-impact aerobics – 455 calories in an hour⅔ cup Ben and Jerry’s PB Over The Top ice cream – 430 calories
Water aerobics – 501 calories in an hourVenti Strawberry Funnel Cake Frappuccino Blended Beverage – 500 calories
Backpacking – 637 calories in an hour1 cup trail mix – 693 calories
High-impact aerobics – 664 calories in an hourPanera Bread Mediterranean Bowl – 630 calories
Running 8 mph – 1074 calories in an hour3 slices of Meat Lover’s pizza – 1170 calories

Studies that do show enhanced weight loss with exercise indicate that it often takes at least 300 minutes of physical activity a week to promote weight loss. This is more than the CDC’s current recommendation of either 150 minutes of moderate-intensity or 75 minutes of vigorous activity each week paired with muscle-strengthening activities at least two days a week. 

More Is Not Always Better

As strange as it might seem, there is some evidence that working out more doesn’t always equate to burning more calories. Above a certain point, the body appears to make adjustments to adapt. So if exercising 300 minutes a week is helping you to lose weight, increasing to 500 minutes a week might not make that much of a difference in your results. In fact, some evidence shows that extreme exercise programs actually reduce resting metabolic rate, despite increased lean tissue mass. 

Weight Loss Means Muscle Loss Without Exercise

Even if exercise alone won’t get you the results you want, it’s still an incredibly important part of your weight loss plan. Why? Because as unbelievable as it sounds, 25% of the weight you lose without exercise is muscle. Yes—if you lose 100 pounds from dieting, you could lose up to 25 pounds of muscle. Additionally, even if exercise alone doesn’t generate weight loss, it does change the body’s contours and is particularly useful for achieving a slimmer waistline. 

Exercise and Maintenance of Weight Loss

Building muscle is also critical for keeping your metabolism up, an important part of weight loss maintenance. A study published in the March 2019 issue of Obesity found that individuals who had lost 30 pounds or more and kept it off for at least a year burnt off at least 300 calories and took an average of 12,000 steps per day. This study used the gold standard doubly labeled water method to measure total daily energy expenditure, which is much more reliable than the methods employed in other studies, such as self-reported food and exercise logs. 

The Stress-Busting and Sleep-Enhancing Benefits of Exercise Matter For Weight Loss

Being mentally strong and emotionally healthy is very important for weight loss, and exercise is an excellent way to bolster your mental wellbeing.

Cortisol

Patients with abdominal obesity have higher levels of cortisol, a stress hormone. Cortisol and other glucocorticoids strongly affect both food intake and energy expenditure, causing us to crave foods rich in fat and sugar and making it less likely that we will be able to burn the calories off. In one study, women who reported being stressed in the previous 24 hours burnt 104 fewer calories than non-stressed women. The women who reported at least one stressor also had elevated insulin levels, which encourages fat storage. 

Sleep

Sleep is also vital for weight loss and exercise does wonders for this aspect of life. In one study, women who slept for five hours a night were 32% more likely to experience a weight gain of 33 pounds or more over 16 years, compared to women who slept seven hours. Surprisingly, the women who got less sleep also ate less than the other women, so food intake isn’t a tidy explanation for the weight gain. 

The Bottom Line

Let’s review: Exercise is extremely important to overall health. As for weight loss, it ensures that you won’t lose massive amounts of muscle and aids in keeping the weight you have lost off in the long-term. However, the calories burnt via exercise will not necessarily add much to every person’s weight loss efforts.

For optimum weight loss and maintenance, you’ll need to work out for 45 minutes every day and burn about 300 calories. For a 200 pound person who is new to exercising, this could mean walking slowly for 30 minutes and lifting weights for 15 minutes.

However, to achieve maximum health benefits, you’ll need to challenge yourself as your fitness improves. It’s critically important to watch what you eat, also, since one smallish-seeming snack can contain more calories than you burn off in your sweat session. 

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