Our studies with several thousand beginning exercisers has consistently shown single-set strength training to be highly effective for improving body composition, increasing muscle strength and reducing resting blood pressure. This is important from a practical perspective because many time-pressured people do not have time to perform multiple sets of each strength exercise.
Eventually, however, standard single-set strength training leads to a strength plateau, requiring some change in the exercise program to stimulate additional muscle development. Such a change could involve more training exercises or more training sets. Unfortunately, both of these alternatives require more training time. For example, performing twice as many exercises requires twice as much training time, and performing two sets of each exercise requires at least three times the training duration, due to the necessary rest period between successive sets of the same exercise.
One time-efficient means for enhancing the strength-building stimulus is known as high-intensity training. Unlike multiple-set training that repeats the exercise bouts, high-intensity training is designed to make each exercise bout more productive. This is typically accomplished by extending the exercise set with a few post-fatigue repetitions to involve more muscle fibers and increase the tissue microtrauma.
A simple means for extending the exercise set is to fatigue the target muscles with your standard weightload, then immediately reduce the resistance by 10 to 20 percent and complete as many additional (post-fatigue) repetitions as possible. For example, let’s say you can perform 10 leg extensions with 100 pounds. At this point, your quadriceps muscles are too fatigued to do another repetition with this weightload. However, if you quickly reduce the resistance to 85 pounds, you should be able to complete three to five more repetitions with the lighter weightload. This extended exercise set has produced two progressively more impactful levels of muscle fatigue with relatively heavy weightloads, all within the parameters of the anaerobic energy system (90 seconds). This high-intensity technique is known as breakdown training because you break down the resistance in accordance with your pre-fatigued level of muscle strength to enable a few post-fatigue repetitions.
A similar high-intensity technique is called assisted training, because an assistant helps you to complete the post-fatigue repetitions. Using our previous example, you have just completed 10 leg extensions with 100 pounds and you cannot perform another repetition on your own. At this point, an instructor manually assists you in the lifting phase of an 11th repetition. Because muscle force output is about 40 percent greater in lengthening (eccentric) actions than in shortening (concentric) actions, no assistance is necessary on the lowering phase of the post-fatigue repetitions. Usually, three to five assisted repetitions are sufficient to achieve a high-level of muscle-building stimulus.
Our many studies examining the effects of high-intensity strength training have consistently revealed excellent results using these and other high-intensity techniques (e.g., pre-exhaustion training, slow-speed training, triple-eight training). In one research program with 48 participants, six weeks of high-intensity training produced an 18-pound increase in muscle strength (average for 12 previously plateaued training exercises), a 2.5-pound increase in lean (muscle) weight, and a 3.5-pound decrease in fat weight.
Fortunately, these highly-reinforcing results were attained from just two weekly exercise sessions of less than 30 minutes each. Unlike performing more exercises or additional exercise sets, the high-intensity training sessions increased the participants’ standard workout duration by only a few minutes. Although time-efficiency is certainly a practical advantage of high-intensity strength training, the major benefit is effectiveness. Almost half of the professional football teams in the NFL use high-intensity training programs to maximize the players strength/muscle development.
Over the years, we have tried many approaches for offering our members opportunities to do high-intensity strength training. Most often we have provided small group sessions or special classes at specific times and places. Unfortunately, it has not always been convenient for members to participate in these high-intensity training programs.
Recently, we have expanded opportunities for supervised high-intensity training sessions to most hours of our fitness facility operation. We have trained several key instructors in high-intensity techniques and allowed interested members to work with them one or two days per week. The participants pay a reasonable fee for these one-on-one exercise experiences (eight weeks, once a week for $60; eight weeks, twice a week for $110), and the instructors receive a higher pay rate ($5 more than their standard hourly rate), which seems to be satisfactory for everyone involved.
Although this is not a high-revenue program for the YMCA, it appears to be the best means for member retention that we have tried. Rather than stagnating on a strength plateau, losing training motivation, and possibly leaving the Y, more and more members look forward to participating in these advanced strength training programs. The time-efficiency, instructor interaction and excellent results make our high-intensity strength training program popular among members, and their renewed exercise enthusiasm has a profound positive effect on our fitness center operation.