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Seven Ways to Design Successful Sprint Workouts for Fat Loss & More Muscle

Sprint training is one of the most profound tools you have to improve your body. Quick sprints build speed, strength, and conditioning in an efficient way. They also trigger muscle building pathways and raise metabolic rate, making sprint training your go-to workout for all body composition goals.

Being so effective, sprint workouts have become increasingly popular to the point where everyone is using them, but often in an inefficient way. People don’t understand how the different energy systems in the body work, or they get rest intervals, volume, and intensity wrong. They end up without the results they expect or they get injured or burned out.
This article will give you some guidelines for designing successful sprint workouts to get fast results.
#1: Start with strides to sharpen running technique.
It’s normal to get all jazzed for all-out sprints after watching Usain Bolt and Allyson Felix torching up the track. Even pictures of ripped, strong sprinters online can get you thinking you need speed.
If you’re just heading out for your first sprint session of the year (or your life), don’t start with all-out sprints right away. Many people get injured, or at the least, very sore from hitting the track for speedy 100s for the first time without some preparation. Instead, start with strides in which gradually accelerate over the duration of your sprint.
Sample workout: Try 100-yard strides on the grass in which you start slow and accelerate into a full sprint by the 50-yard mark. Over time, work on getting up to full speed sooner and maintaining technique through the finish line. Strides are also useful warm-ups once you get into 100 percent intensity track sprints.
#2: Use hill and sled sprints to reduce soreness and train acceleration.
Hill sprints allow you to work on technique, power, and conditioning, without the risk of over-striding or the need to decelerate at the end of your sprint, which is when most people get injured.
Hill sprints also apply a large overload, but at a reduced distance. You don’t have to run as far when going uphill, which can be useful for boosting morale and enthusiasm when all you can think of is how hard your last sprint workout was.
Sled sprints are another useful alternative to full-on sprinting. Pushing a sled removes the eccentric component in the same way uphill running does and it requires reduced speeds for less risk of straining a muscle.
Sled training will teach you to accelerate safely as well. This is key because novices often don’t know how to switch into that high, all-out gear. For example, when sprinters added weighted sled training to their workouts for 4 weeks, they were able to reach top speed sooner during free sprints. They also increased maximal speed by 1.3 percent compared to a group that just did traditional sprint workouts.
Sample workout: Do weighted sled runs of 15 to 25 meters. No need to go further because form and intensity tend to deteriorate. Pair short sled runs with regular 50- to 100-meter sprints to take advantage of the fact that the lower body muscles are already activated.
#3:  Rest intervals must allow for running speed to be maintained.
Just as with strength training, volume and intensity are inversely related.  The key to producing adaptations is to modify rest intervals and possibly volume to make sure you maintain sprint quality and speed.
Sample workout: When doing maximal 30-second sprints, strength trained individuals who are new to sprinting and want to lose body fat will benefit from 4 repeats with nearly full recovery, which will likely take 3 to 4 minutes. This will allow you to develop a base if you are new to sprints. As you gain conditioning, you can increase the number of repeats, and you can shorten your rest periods to continue to elicit adaptations.
Once you have a decent level of conditioning, you’ll reap the greatest body composition benefits from working at an intensity so that the body uses the anaerobic energy system and doesn’t shift into aerobic mode. In simple terms, if it doesn’t “burn” or feel challenging, you’re not working hard enough.
#4:  Train for increased power with super short sprints.
All-out short sprints teach your brain to recruit a full range of muscle fibers in the same way maximal lifting does. It’s most useful for athletes who want to boost power and speed. But anyone with basic strength can benefit and short sprints can be fun, fast, and make you feel on top of the world.
Energy-wise, short sprints train the phosphagen system that relies on creatine phosphate (CP). Energy production increases up to 100-fold but it only lasts for about 6 seconds, so to train maximal speed and power, intervals need to be short and allow for full recovery.
When you shorten the rest period so CP isn’t restored, you’ll tap into the glycolytic pathway, which can be beneficial for boosting conditioning and hormone response.
Sample workout: Short sprint workouts of 8 sprints for 5 to 10 seconds (40 to 80 yards) at top speed. Do 2 to 3 sets, with 3 minutes rest between sets.
#5: Use quick repeats with short rest to build muscle & improve conditioning.
By shortening the rest interval dramatically in between sprints, you still train power and improve anaerobic conditioning. This type of conditioning also provides a large hormone response, which can promote fat burning and lean muscle development.
It’s ideal for combat athletes like wrestlers, judokas, and boxers, but they will also benefit the trainee who just wants to be more athletically awesome.
Sample workout: Six to ten repeats of 35-meter all-out sprints with 10-seconds rest. With a practically non-existent rest period, you’ll be using the glycolytic energy system and your body will be burning energy at a high rate.
This workout comes from a study done by competitive wrestlers twice a week for 4 weeks in order to increase maximal power by 5 percent and increase time on an exhaustive exercise test by 32 percent from 356 to 471 seconds.  They also had higher testosterone and a decrease in cortisol of 12.6 percent, which is favorable for improvements in body composition.
#6: For fat loss, use sufficient work bouts so that you get the body to start producing lactic acid.
Sprints are an excellent training tool to lean up by reducing body fat and building muscle. Anyone can benefit, including distance runners, lifters, strength athletes, and recreational trainees.
Workouts should last between 10 and 30 minutes (including rest intervals), depending on intensity. The sweet spot for most trainees is 20 to 25 minutes.
Any workout longer than 30 minutes is NOT an anaerobic interval workout. Although workouts lasting less than 10 minutes have been touted in the media as all you need, the sad reality is that a workout this brief may improve health and general fitness, but it won’t significantly change your body.
Four to ten minute workouts will improve insulin sensitivity and fat oxidation but they don’t lead to lactic acid buildup, a significant hormone release, or burn many calories. That’s where longer interval sessions come in.
Sample workouts: Try 6 to 8 repeats of 150 meters with 90 seconds rest. Each week shorten your rest interval by 15 seconds. Time all your intervals to make sure you sustain work intensity for the duration of your repeats.
#7: Use 200 to 400-meter sprints to build speed endurance, put on muscle, and burn fat.
These longer sprints are where we lose a lot of people. They’re hard. They challenge your physical capacities. Don’t be scared away by this. Longer sprints are well worth the effort because they force the body to adapt quickly and dramatically.
These workouts will teach you how to dig for that extra effort, while adapting the body to shift between the lactic acid, carb burning energy system and the aerobic fat burning system—a metabolic state that is both ideal for performance and useful for fat loss.
Sample Workouts: Try 6 to 8 reps of 200 meters with 2 minutes active jogging recovery. Taper down to a 1-to-1.5 work-to-rest ratio over time.
Descending sprints are a popular option because the distance gets shorter as the workout progresses. Trainees tend to rate such workouts as easier. Try 400, 300, 200, 100 meters with 4-minutes rest after the first sprint, 3 minutes after the second, and 2 minutes after the third. Then rest 4 minutes and repeat.