“Where does the power come from to see the race to its end?“
—Chariots of Fire
Do sprints to lose fat, build muscle, improve your health, and live a more excellent life. Sprint training is a powerful tool that gives you back considerably more in terms of health benefits than the effort required.
Sprint training IS mentally challenging due to the physiological stress it causes, but it’s well worth the effort: It takes much less time than the next best exercise models, which don’t even convey as many advantages. Better heart and lung health, improved circulation, better cognition, improved metabolism, the optimal hormonal environment, and the ideal body composition are just a few of the reasons everyone should do some form of sprint training.
It should be noted that there is a difference between all-out sprinting (moving at your fastest possible speed for a certain distance) and high-intensity training (alternating bursts of very intense activity with intervals of rest), both in terms of protocols and training outcomes. Luckily, the health benefits and fat loss come from doing either one, though with slightly varied returns that are related to the effort you put into your workouts. Get best results by programming according to your goals, physical limitations, and abilities.
Reason #1: Lose Fat Fast With Sprint Training
Research shows that repeated sprint training is the only form of conditioning to produce significant fat loss, and it does so in an amazingly small amount of training time. Scientists write that compared to steady-state aerobic training, which produces disappointing fat loss, sprints are much more effective for fat loss in a shorter time.
A classic 1994 study is indicative of this: Participants did either 20 weeks of steady-state aerobic training or 15 weeks of intervals (15 sprints for 30 seconds each). The interval group lost nine times more body fat and 12 percent more visceral belly fat than the aerobic group.
Depending on training status (trained, untrained, or athlete), initial body composition, and protocol, sprint training can decrease body fat by 10 to 20 percent over a typical 12-week program. For example, a protocol that has been tested repeatedly on overweight men and women that uses 60 all-out 8-second cycle sprints with 12 seconds rest led to about 2.5 kg fat loss and 1 kg muscle gain in both men and women.
The benefits of sprints are evident quickly: A 2010 study found that just 6 sprint sessions of six 30-second all-out cycle sprints with 4 minutes rest over 2 weeks led to a leaner waist by 3 cm., and a much greater use of fat for fuel. It’s not surprising that the men didn’t actually decrease body weight over the short study period since sprints will trigger muscle building just as they start burning body fat. But the shrinking waistline and increased fat oxidation would very likely lead to more dramatic fat loss if they kept the training up for a few months.
Reason #2: Build Muscle & Target Fast-Twitch Fibers
Sprint training will help you build muscle and it preferentially increases the size and strength of the powerful, fast-twitch fibers. Studies show sprinting enhances protein synthesis pathways by as much as 230 percent! With the right nutrition and recovery, this will lead to muscle building, allowing you to look leaner and run faster.
In addition, sprint training has repeatedly been shown to increase anabolic hormones that improve body composition. For instance, male wrestlers who did short-sprint training (six 35-meter sprints with 10 seconds recovery) significantly increased testosterone and decreased cortisol, leading to a favorable ratio between the two hormones for muscle building and fat loss.
Women won’t experience the same increase in testosterone, but sprints will increase growth hormone (GH), burning fat and building muscle for a strong, lean outcome. In fact, some studies indicate that women have higher baseline GH and may get a bigger boost in GH in response to intense training, although more research needs to be done.
Reason #3: Increase Endurance & Work Capacity
Studies show that sprint training is more effective than steady-state endurance training for improving endurance capacity, maximal oxygen uptake, and time to fatigue. This is because repeated intervals at a high intensity lead to the following adaptations:
- They require the body to use energy more efficiently by increasing the amount of glycogen that can be stored in the muscle by as much as 20 percent.
- Sprints “train” the body to burn fat for fuel, preserving muscle glycogen and prolonging work capacity.
- Intervals increase the body’s ability to remove waste products during exercise, leading to a 50 percent increase in what is called the muscle buffering capacity.
- Since sprints build muscle and target the fast-twitch fibers, they increase your speed and power, leading to a faster running or cycling speed. For example, one study found that trained cyclists who did six 30-second all-out sprints increased endurance speed, and decreased time trial performance by 26 percent more than a steady-state training group that did their regular workouts.
Reason #4: Improve Heart Health
Comparison studies between interval and endurance training repeatedly show better cardiovascular outcomes from intervals. For example, a 2011 study in overweight women showed increased stroke volume and lower training and resting heart rate after 4 weeks of cycle sprint training. A similar 2008 study showed better arterial structure, with a decrease in chronic inflammation that damages heart function, from sprints than from aerobic training.
Other cardiovascular benefits include a significant decrease in systolic blood pressure. Of course, for the elderly who need to prioritize both cardiovascular health and functional mobility, interval training is preferred because it can help then build the fast-twitch muscles to prevent falls and fractures, while improving heart function. Aerobic exercise should be secondary since it leads to a loss in muscle and explosive power in the long term.
Reason #5: Improve Insulin Sensitivity & Energy Use
A number of studies show any time you alternate intense bursts of exercise with rest periods, you will improve insulin sensitivity and blood sugar tolerance. This is partly because sprints decrease chronic inflammation and partly because the cells must adapt to more efficiently produce energy to keep you going.
Sprints improve insulin health in the young, old, overweight, diabetic, and folks with metabolic syndrome. As mentioned early, they increase fat burning during training and lead to a measurable post-workout calorie burn (called EPOC). Throw in the fat burning hormone response to training and you have a potent fat loss environment.
For example, a 2006 review showed that protocols that are more anaerobic in nature, as sprints are, produce higher EPOC than steady-state training because the trained muscle cells must restore physiological factors in the cells. This translates into a lot of extra energy expenditure to help get you lean.
Reason #6: Improve Conditioning, Circulation & Lung Function
Sprint training is better for improving pulmonary lung function than aerobic exercise. It will give you better conditioning so you can run up the stairs or chase after your kids without getting winded.
For example, a 23-minute sprint workout that included five 1-mintue intervals with 3 minutes rest significantly improved lung capacity compared to an aerobic protocol. Sprint participants also lowered cholesterol and improved circulation.
Reason #7: Improve Cognition, Brain Volume & Prevent Depression
It’s no surprise that sprint training makes your brain work better and can make you happier since just about every form of exercise has been shown to reap some mental benefits. Sprint training leads the pack: It decreases inflammation in the brain, improves hormone balance, leads to better mobility, and makes you feel energized and capable after you blast through a series of repetitions that test your abilities.
Reason #8: Save Time, While Building Mental Toughness
Sprint training can and needs to be done in a short amount of total training time. You can’t keep up the intensity level necessary for your intervals to be called sprints for much longer than 20 minutes. And you’ll get the best fat loss, muscle building and health results from keeping it short, simple and intense. You don’t need crazy volume here, you just have to train hard and with intention.
Sprints are hard. They hurt. There will be moments of doubt when you are in the middle of a sprint workout. The pain and uncertainty in your ability to finish your workout is all in your head. You must not give in.
By pushing through the physical discomfort and pain, you will build confidence in your physical and emotional ability. You will accomplish something not many other people can do. You will get a lean, muscular body, and improve your health, putting you ahead of the biggest health threats that face you as you age.
Start a sprint training program today. Now is the time.
“One of the illusions of this life is that the present hour is not the critical, decisive hour. Right it on your heart that every day is the best day of the year.”
–Ralph Waldo Emerson