The Science of Losing Fat, Preserving Muscle & Doing it in 20-Minutes
Imagine stepping on the scale and it reads: Congrats! You’ve Lost 10lbs of fat, muscle & bone.
Who wants to lose muscle and bone?
Unfortunately losing weight can mean losing more than just body fat. So if you want to lose fat and only fat while adding lean muscle to your body, this article is for you.
It’s Simple: Muscle Burns Fat
If you want to lose fat efficiently, you must know this: Muscle burns calories.
By adding more lean muscle to our bodies, we increase our resting metabolic rate, or the calories we burn on a daily basis.
So, how do we add more muscle to our bodies?
In fact, strength training is more effective in burning fat than most “aerobic” activities because the added muscle helps you burn calories, even while you rest. Aerobics can burn a lot of calories but only in the moment of the activity.
Strength training research shows that women’s resting metabolism actually decreased 75 and 103 calories per day with “aerobic” and diet-only changes.
With a slower metabolism, maintaining fat loss becomes more challenging.
With more muscle, maintaining fat loss becomes easy.
But I’ve Lost Weight with Aerobics Before…
Many of our clients and even our Trainers love to do aerobics and believe it or not, we fully support it – especially if it's something you love to do.
But for many, aerobic activities like running feel like a chore, and people do it because they believe it's absolutely necessary to lose weight.
A 2007 study put overweight and obese women through 25 weeks of a restricted diet that was complimented with either “aerobic” activity, or strength training, or no exercise at all.
Both the strength training and “aerobic” groups lost 26 lbs. of fat, slightly more than the women who only dieted.
However, here’s the difference: the strength training group not only maintained their lean mass (muscle, bone, water, and other organs), but actually gained a little.
The “aerobic” and diet-only groups lost two and three pounds of lean mass.
Remember, if your weight is decreasing, are you really getting to your target destination? In other words, are you losing just fat, or are you losing fat along with muscle and other tissues?
Losing weight does not necessarily imply that you will be leaner WITH better muscle tone, and that’s what you really want.
How to Burn Fat in 20 Minutes
Strength training is often said to transform the body into a calorie-burning machine. If so, can you get the same metabolic effect from a 15-20-minute workout using only one set for each exercise as you would from a longer, multiple-set session?
You probably know the answer is yes, but here is the research to prove it:
A recent study used two different protocols:
- A full body workout using one set, each performed to muscular fatigue
- A full body workout using the same amount of exercises, also working to muscle fatigue, but featuring three sets of each exercise
The researchers in the study measured the calories expended at rest each day for a week after both workouts.
There was NO difference between the two groups. A workout using one set per exercise increased metabolism to the same degree that a three-set routine did for 24, 48, and 72 hours afterwards.
The study also showed the higher calorie expenditure rate wore off 96 hours after the workout.
By strength training twice a week, your resting energy expenditure is likely elevated all the time. By the time one session's effects wear off, another session occurs and the process starts over.
Finally, the researchers noted another bonus that you can relate to: saved time.
The one-set workout took an average of 16 minutes compared to 37 for the three-set trial. Essentially, you can save 21 minutes and achieve the same boost in metabolism by performing a full body workout with only one set per exercise.
If you’re going to get similar results from working out for 16 minutes as you would for 37 minutes why would you waste any time and work out longer than necessary?
20 minutes of slow-motion strength training is all you need to be efficient at burning fat and if you are training twice per week, you can experience this calorie-burning benefit on a perpetual basis.
Don’t Forget Diet
Improving eating habits has the most influence on losing weight. However, diet by itself can also lead to indiscriminate weight loss: fat, muscle, bone, water…it all goes.
Thankfully, there is a way to minimize or eliminate muscle loss during diet-induced weight loss: strength training.
Changing eating habits is the most influential method for losing weight, and strength training is the most effective method ensuring that the lost weight is only fat.
If losing fat is your goal, the solution is simple:
- Slow-motion strength train to muscle fatigue, twice a week
- Eat a diet conducive to your needs and to lose fat
- Limit aerobic activity
Hunter, Gary R., et al. “Resistance Training Conserves Fat-free Mass and Resting Energy Expenditure Following Weight Loss.” Obesity 16.5 (2008): 1045-1051.
Stiegler, Petra, and Adam Cunliffe. “The role of diet and exercise for the maintenance of fat-free mass and resting metabolic rate during weight loss.” Sports Medicine 36.3 (2006): 239-262.
Heden TT. One-set resistance training elevates energy expenditure for 72 h similar to three sets. Eur J Appl Physiol 111: 3: 477-484,2011.
Catenacci VVA. Physical Activity Patterns in the National Weight Control Registry. 16: 1: 153-161, 2008
Jordan Thomson is passionate about fitness and helping others live sustainably healthy lives. Jordan joined The Perfect Workout in 2013 as a Personal Trainer in Newport Beach, CA. Since then she has helped expand our company with new studios in Chicago, IL and led teams of trainers in Philadelphia as well as Los Angeles. Now she serves as a creative mind within the Marketing team to help spread our mission to revolutionize the way people exercise.