By Joli Guenther, MSSW, NASM
We all know that finding time to work out is tough this time of year, but if burning off those holiday calories has you envisioning long sessions on your treadmill or elliptical, think again. Research is showing that efficient, challenging and short interval workouts are highly effective at burning fat, building muscle and bringing home health benefits for your metabolism and energy levels.
So just how short of a workout are we talking? HIIT (short for High-Intensity Interval Training) workouts are generally between nine and 20 minutes, meaning you can reap big benefits from your home fitness routine in less time than it would take to drive to the gym.
Although these workouts are short in duration, they're anything but easy. The key is to push your body at maximum or near-maximum effort during your interval peaks and to continue at a fairly high level of aerobic effort (60 to 70 percent of your max heart rate) during the recovery windows. Early research on HIIT workouts was pretty specialized, but recent studies have created workouts that can easily be duplicated on your home treadmill, elliptical, or recumbent bike. A 20-minute workout is ideal, but even 10 minutes will leave you with benefits that include increased cardiovascular capacity, revved up metabolism, post-workout calorie burn and lowered insulin resistance.
Ready to Go?
HIIT workouts are seriously convenient and can be completed on your treadmill, recumbent exercise bike or elliptical machine. The general pattern of the workout is to start with a warm-up of three to five minutes, followed by five to 10 minutes of intense intervals, and finishing with two to five minutes of cool-down.
Your warm-up and cool-down will be the same as your regular exercise, but performed at a slower easier pace (think walking, jogging, or easy cycling).
The intervals should alternate approximately one minute of your highest effort (90 to 100 percent of your maximum heart rate) with recovery periods of approximately two minutes during which your heart rate returns to 60 to 70 percent of your maximum.
As you get more fit, you can increase the peak intervals to as much as two minutes and reduce your recovery intervals to as little as one minute. If you're new to interval training and would like a week-by-week program, check out this link for more details and descriptions of putting HIIT into practice.
How hard should you work?
If you don't know your max heart rate from previous training, you can estimate it by the formula 220-your age. For example, a 40-year-old exerciser would have an estimated max heart rate of 180. Maximum heart rates do vary by individual, so if you reach a heart rate during your training that is higher than your estimated maximum, then your individual maximum heart rate is at least that high and you should use that heart rate in designing your HIIT program. Of course you should always consult your physician if you have any concerns or questions about what is safe for you.
Is HIIT right for you?
HIIT workouts are challenging but doable if you've been working out regularly and are capable of working out for 20-30 minutes at an aerobic level (60 to 80 percent of your max). If you're just getting started on your home fitness program, check in with your doctor before trying a HIIT plan. You can also modify the approach slightly for a few weeks by working up to 80 or 85 percent of your maximum heart rate rather than the full 90 to 100 percent typical of HIIT.
If you're feeling seriously uncomfortable during the recovery portions of your workout and are not able to get your heart rate back down below 70 percent of your max, try lengthening your recovery period or scaling back your workout. If this doesn't help, proceed directly to your cool-down before finishing your workout to avoid dizziness that can come from abruptly ending your workout.
You'll get serious benefits from including a HIIT workout in your routine twice a week (just the thing to keep you exercising on busy days this Holiday Season). For the seriously motivated, try adding in a third interval session with at least a day between sessions. Then mix it up with some strength or endurance training on days you have more time.
Looking for more info?
Wikipedia provides a good overview of what HIIT is and the research that has been done on different approaches to this method of training. Science Daily also offers a great discussion of research that is more applicable to a home exercise setting.
Weigh In: What's your approach to squeezing in your workouts at this busy and dark time of year? Does a HIIT approach fit into your day?