I've been using Sprint-8 intervals for years with my clients and friends to optimize fitness gains and weight loss. The "Sprint-8" combines a 30 second "sprint" with a 90 second "rest" period which is then repeated 8 times for one workout. There is a two-minute warm up and two-minute cool down.
The Sprint-8 interval protocol established by Phil Campbell has been the best protocol I've found for consistent weight-loss results. The Sprint-8 intervals are extremely reliable and fairly easy to learn in terms of the mechanics of the intervals and how to do them. Recently, a web follower and friend of mine attended a workshop in Indiana with Sprint-8 creator Phil Campbell/author of "Ready, Set, GO! Synergy Fitness." My friend sent me the following updates from Phil's workshop which are now also included in the 2nd edition of Ready, Set, GO! These updates should help us further optimize the efficiency of the Sprint-8 intervals—especially if you are over age 40 and trying to lose weight. You can read the latest edition of Phil's book for more info, but here's the bottom line:
In Short…think quality NOT quantity. We are not doing them hard enough! You should not be doing more than 8 intervals—ever—just do them harder if you truly want to optimize the metabolic effects for weight loss. The harder the interval, the more you increase HGH for the two hours after the workout—HGH "decreases" in people as they age, so this HGH is thought of as a "youth" hormone for anti-aging. HGH occurs naturally in the body and can be optimized with proper training, but today many people take short cuts by getting HGH supplementation which are controversial. You need to adjust your dietary intake to optimize the post-workout HGH production in the synergist window (Human Growth Hormone increase). If you are middle age and needing to lose weight, avoid carbs two hours after Sprint-8 and ingest 25 grams of protein to maximize HGH production—this opposes the "standard" post-recovery recommendations to ingest a 4/1 carbohydrate/protein ratio. *(I would recommend "natural" protein powder because it is healthier—see protein link below.) If you are younger and your objective is to refuel for ongoing hard workouts, then using the standard 4/1 carb-to-protein ratio is best.
More Details for Middle Age 40+ populations needing to lose weight with the Sprint-8 Intervals:
- Sprint hard enough so that by 15 seconds of the 30 second interval you are ready to quit—but don't!
- Limit sprint length to only 30 seconds. Go harder—not longer.
- Limit total intervals to 8. Use more intensity—not more volume.
- Do not eat a high-fat meal before Sprint-8. Eating some "good" carbs to fuel before workout is fine.
- Take 2 grams of L-Glutamine 60-90 minutes before workout. *I'm not a person that pushes supplements, but I'm reporting what Phil says will optimize HGH with the Sprint-8. I have included a WebMD link on L-Glutamine, but basically this is used for muscle wasting in HIV/AIDS patients or cancer patients. There are those that take it in excess as a supplement, but the 2 gram recommendation is well under the 40 grams per day limit cited by WebMD. Ultimately, it is the user's choice, but I have provided the documentation so you can make an educated decision.
- NO sugar or carbs for 2 hours after workout!!! Ingesting carbs during post-workout with Sprint-8 will stop HGH production. The idea is to "increase" HGH production and your metabolism—not decrease!
- Ingest 20-25 grams of protein soon after workout. Most sources give a 30 minute to 2 hour window for post-workout recovery fueling. I would say ingest the protein within a 30 minute window following the workout.
- Never perform Sprint-8 Intervals more than 2-3 times per week. Think quality—not quantity!
In reality, you should NOT be able to do any other work of significance after your Sprint-8 workout is complete—you should be DONE. If you feel like doing a bunch of other stuff—you have not done them hard enough!!! Oh…for those of you not familiar with the Sprint-8 Interval Protocol…total time from start to finish including warm up and cool down is just 20 minutes! Yes—you'll get more benefit in 20 minutes than the people next to you grinding out the 45-60 minute workout which likely is not doing much to optimize their metabolism or weight loss. I've seen people lose 40-60 pounds on the Sprint-8 in well under 12 months.
Mode & Mechanics: For the general population, there are only two modes I recommend—the elliptical trainer or Concept2 Rowing Machine...a high-quality stationary bike like a Spinner or equivalent can also work but not as well as the first two in my opinion. Treadmills won't work because they will take too much time to adjust for each interval—there is NO TIME to adjust anything—you have go GO when it is time to GO! You "could" do these running on a track, but most people are not fit enough to do this without getting hurt or straining their hamstrings. Other machines like stair climbers, etc. are also NOT a good choice because of the time required to adjust them for higher speed and intensity during each interval. We run the elliptical trainers in manual with NO resistance—we use "speed" to increase heart rate—not resistance. A Spinning bike will need a slight amount of constant resistance, but again, use SPEED to increase your heart rate rather than heavy resistance. I have done something close to the Sprint-8 using stairs or hill repeats outside, but again, most people are not fit enough to do this off the machine. The e-trainer and rower will do a great job for you, so get started!
Exercise Induced Asthma (EIA): Doing really hard sprints or exercise efforts with minimal warm up can cause some EIA for some individuals--and if not actual EIA, other breathing difficulties. One of my friends that uses the Sprint-8 has EIA. He must do a longer warm up and cool down to allow the lung tissues to function more normally, so if you have EIA, please consider adjusting the pre and post workout recommendations. The longer warm up and cool down (until HR drops under 120 for my friend) should help you avoid the EIA that can be trigger by sudden sprints without much warm up. Remember--the regular warm up and cool down for the Sprint-8 is only 2:00 for each.
Safety: If you can't sprint for 30 seconds without killing yourself—then don't! I've had many people start the Sprint-8 intervals with minimal fitness—just modify. Do what you can do safely. If you can only go hard for 5 seconds, then go hard for 5 seconds, and do your best for the remaining 25 to hang on. But remember—you'll never optimize the HGH production and metabolic effects by going easy or at a moderate pace or by only going hard for a few seconds. To get the most out of the protocol, you need to go HARD for the full 30 seconds. For most, this will become quite a challenging goal—just to work hard for 30 seconds straight without giving up. The 90 second "rest" period is also critical because it has to be a quality "rest" heart rate i.e. not under 65% of your heart rate range—see my Sprint-8 handout or Ready, Set, GO! for more information…Enjoy!
Related Links & Information:
Read my "Interval Training" Web Section complete with Sprint-8 summaries:
Ready, Set, GO! Synergy Fitness (by Phil Campbell creator of Sprint-8 interval protocol):
WebMD Human Growth Hormone (HGH) Link: Do NOT take HGH Supplements!!! Raise them naturally with the correct exercise intensity.
"Natural" Protein Powder Handout: (The Lean Berets)