Thinking of getting lean? Confused about how to get lean, build muscle, and look hot?
If you're a regular reader, you probably have the sprints-weights-aerobics for fat loss hierarchy all figured out. However, some people are still confused about what the priority is if they want to lose fat and optimize body composition.
Research shows that aerobic exercise produces negligible fat loss whereas anaerobic modes of exercise such as strength training and sprinting are powerful tools for optimizing body composition because they burn fat and build muscle.
In order to avoid continued confusion, the following six points clarify how to use the different types of exercise to get the best results.
#1: Aerobic training can help you lose fat if you are just starting to exercise. Although it is not the most effective type of exercise for fat loss, aerobic-style cardio can work if you are new to exercise.
For example, in a recent study from Duke University, sedentary, out of shape, overweight people performed fairly intense (80 percent of max heart rate) aerobic exercise for 40 minutes 3 times a week for 8 months and they lost significant body fat.
The key to getting results with aerobic exercise if you're a novice is to be consistent and monitor food intake to make sure you don't compensate for exercise by eating more. In addition, adding a strength training program to your routine will help you keep off any fat you lose for the long term.
#2: In the long run, aerobic training is useless for fat loss. In the Duke study the aerobic group only lost an average of 1.6 kg of fat (not much!) and they didn't build any muscle, which is where we see the fault in the plan. By decreasing body weight, the aerobic group lowered metabolism, while improving aerobic conditioning.
They were “in shape” and thinner, but no stronger, and they had decreased their resting energy expenditure. In order to maintain that fat loss, they would need to eat less, change their macronutrient proportions, or exercise longer and more intensely.
For example, in a 2006 study of runners, only the runners who tripled their weekly mileage from 16 km/week to 64 km/week did not gain fat over the 9-year study. That's a huge increase that would naturally triple the amount of training time required to prevent fat gain.
#3: Resistance training done right can produce greater sustainable fat loss. An unfortunate problem with research studies that test the effect of exercise modes on body composition is that they aren’t very practical:
- They are time limited, when in reality, exercise is a continuous endeavor.
- Training protocols tend to be poorly designed. For example, in the Duke study, a resistance protocol was tested for its effects on fat loss, but it was set up to fail because the rest/set/rep scheme used was not very vigorous.
- Training volume may not be equal or ideal. In the Duke study there were three groups, all with different volume and intensity, so the results can’t distinguish the “optimal” program. Instead, the results show that if you only have a little bit of time to train, you’re new to exercise, your only goal is fat loss, and it’s time limited (as in you are losing fat for a wedding and that’s it), then aerobic exercise is not a bad choice compared to isolation exercises on machines!
- Another pro of aerobic exercise would be that you really enjoy it. If so, that’s great, have at it, but if your goal is fat loss, consider adding some intervals and weights to get better results. Check it out…
#4: Doing smart anaerobic training, you can lose more fat quicker, while building muscle so that you raise your metabolism. For example, in a study of women that compared an anaerobic resistance training program with an aerobic protocol, the heavy load training group lost nearly 5 kg of body fat, gained about 3 kg of muscle, and had dramatic increases in strength. The women who did the high rep, aerobic-style lifting program had no change in body composition.
The benefit of building muscle is that your hard work lasts longer if you quit exercising: A study that tested what happens when subjects stopped exercising for 3 months after doing aerobic or resistance exercise found that a resistance training group maintained improvements in strength, muscle, and cardiovascular fitness longer than an endurance group.
The benefit of resistance training is even more pronounced for people who are in shape. In trained male athletes, a 6-week heavy load strength training program with multi-joint lifts (deadlift, squat, military press, chin-up, and bench press) allowed them to lose 1 percent body fat , while gaining 1.3 percent muscle mass for a dramatic improvement in body composition.
Compare that to the Duke study: The aerobic group also lost 1 percent body fat but gained no muscle, resulting in a less valuable body composition; the resistance group lost 0.65 percent body fat percent and gained 2 percent muscle; the concurrent group lost 2 percent body fat and gained 1.4 percent muscle mass.
The most favorable body composition was seen with the concurrent group, but it took double the time. When you consider the long-term effect of such a time-consuming, stressful program, it certainly is suboptimal.
#5: Prioritize anaerobic over aerobic training to avoid “interference” and overtraining. Over the long term, the body responds to aerobic training by losing muscle because it causes elevations in the stress hormone cortisol, which degrades tissue. Anaerobic training typically leads to gains in muscle and loss of fat due to an increase in muscle protein synthesis and greater insulin sensitivity and energy expenditure.
The negative effect for aerobic exercise appears to be exponentially greater the more time you spend training. For instance, in long-term endurance athletes, hair cortisol levels were found to be much higher than in a sedentary control group.
Even in non-athletes we see evidence of this “overtraining” effect with greater volume: In a study that compared the effect of 13-weeks of aerobic training in overweight men, a group that did 30 minutes of training lost 4 kg of body fat, whereas a 60-minute training group lost only 3.8 kg of body fat. Doing double the amount of exercise resulted in slightly less fat loss.
“Interference” is similar to overtraining and occurs when two different types of training are performed concurrently. Simply, research shows that aerobic exercise "turns off" muscle building pathways, whereas anaerobic training with sprints and weights shifts them “on.”
#6: The bottom line is to do sprints and lift weights to improve your physique. Focus only on anaerobic training and give it all you’ve got.
Sprint training appears to be the most effective way to do this over the short-term. A popular 20-minute sprint cycling workout has been found to lead to 2 to 3 kg of fat loss in overweight, untrained men and women. Try this protocol that used 8-second sprints with 12 seconds rest.
More experienced trainees will benefit from running sprints on a track. A Canadian study found that trained individuals who did six 30-second all-out sprints with 4 minutes rest lost an impressive 12.4 percent body fat after spending less than .75 of an hour actually sprinting. An aerobic group only lost 5.8 percent body fat but they spent a whopping 13.5 hours training.
Suggestions for developing the best resistance program include the following points:
- Multi-joint lifts such as squats, deadlifts, lunges, split squats, step-ups, chin-ups, and chest presses in every training session.
- Train with a higher volume—work up to more than 4 sets per exercise. Shoot for 24 to 32 total sets per training session.
- Train with a higher intensity—include some training in the 70 to 85 percent of the 1RM range.
- Include short rest periods (30 to 60 seconds) and count tempo for every lift so that you apply a specific amount of tension to the muscles. In general, opt for longer (4 second) eccentric tempos and short or explosive concentric tempos.
- Shoot for 3 to 4 hours of total training time per week, which includes resistance training and a few short sprint sessions.