High-Intensity Training and Weight Control
By S. Franckowiak, B.S., and K. Fontaine, Ph.D.

In this article we will describe the potential role that a rationally-derived program of strength training can play in weight loss efforts, and outline some broad recommendations to enhance its effectiveness.

In order to lose fat, you must create an energy deficit (i.e., expend more calories than your body needs to function). Unfortunately, when you create such a caloric deficit you do not lose just fat. That is, the body takes energy from body tissue indiscriminately. In fact, any diet produces not only fat loss, but lean tissue loss as well. A recent analysis by Ballor and Poehlman (1994) indicated that an average of 28% of the weight lost among dieters who do not exercise is actually fat-free mass (i.e., lean tissue) compared to 13% among dieters who performed primarily aerobic exercise. Indeed, if the caloric deficit is severe enough (e.g., very low calorie “fasting” diets) even organ tissue and bone is lost. Moreover, since calorie restriction is an unnatural act, the body begins to adapt by reducing resting metabolic rate (RMR).

This means that you have to create progressively greater caloric deficits to continue to lose fat at a consistent rate. Given this, the primary goal for utilizing strength training in conjunction with weight reduction activities is to preserve fat-free mass while losing body fat. The preservation of fat-free mass also serves to keep the metabolic rate as high as possible so that fat loss can be promoted even with a relatively modest level of caloric restriction. In addition, strength training may be a useful strategy for maintaining the fat loss (i.e., keeping the weight off) once the person has reached their goal.

That is, developing as little as one pound of muscle tissue after calorie restriction will allow a moderately active person to consume an additional 50-100 calories a day. In fact, adding three pounds of muscle increases metabolic rate by about 7%. The bottom line is that gaining lean muscle is highly desirable because muscle is metabolically active (i.e., it needs a modest amount of calories to survive) while fat is not.

Let us look at you can use a HIT approach to maximize the short and long-term effectiveness of your weight loss/weight control efforts. Note that our broad suggestions will need to be modified somewhat given the unique circumstances of a given individual.

Intensity

Intensity is the name of the game in strength training. You have to work hard enough to set the growth machinery into motion. You need to slowly and gradually increase the intensity of your workouts (perhaps over several weeks) until you are physically and mentally capable of working an exercise with the required effort.

Brief

The anaerobic workout should only be as long as required to stimulate the growth, or the maintenance of fat-free mass. Most often, individuals have time constraints make it difficult to participate in a regular strength training routine or that they have no interest in spending hours in a gym . Making workouts short
and intense should provide necessary stimulation of muscles without producing disinterest or boredom. We suggest single work sets of 3 to 5 multi-joint exercises which focus on the larger muscle groups
(legs, hips, back). Weights can usually be lifted using approximately 60 to 80% of their initial 1RM and slowly progressing from there.

Workouts should be conducted at a rather brisk pace and should be kept to less than 30 minutes. We would not necessarily discourage low intensity aerobic activity after the  weight training, but if the weight training was of sufficient intensity, it is unlikely you would want, or becapable of performing, a great deal of aerobic exercise.

Infrequent

One reason many people are anti-strength training is the belief (propagated in the popular muscle magazine) that you must train very long and frequently (1-2 hours, up to 6 days a week) in order to make progress. The brevity and relative infrequency of HIT training is very appealing to most people. We would suggest training three times a week initially in order to develop the motor skill necessary to adequately and safely perform the movements. As the intensity increases, the frequency of training should be reduced to ensure proper rest and recovery.

Safety

HIT, being a high intensity low-force training protocol, is very safe, provided proper exercise technique is used. Make sure you acquire the skill to perform each exercise properly before you train alone.

Stressing slow controlled movements with good form will lessen the chance of injury. Obviously, the use of machines would be preferred because they require less skill to execute the movement.

Reprinted with permission of Exercise Protocol.