It is interesting to note that adult and senior men add about 3 to 4 pounds of lean (muscle) weight after 2 to 3 months of strength exercise (15, 17, 18), whereas adult and senior women gain about 2 to 3 pounds of lean (muscle) weight over the same training period (3, 18). Although the rate of improvement is almost the same, men typically replace more muscle than women during a given time period because they generally have greater body mass.

On average, previously sedentary seniors can replace approximately 3 pounds of muscle after about 3 months of regular resistance exercise. Further, 3 pounds more muscle tissue increases resting metabolic rate by approximately 7 percent in older adults. Additionally the senior exercisers in these studies averaged about 50 percent greater muscle strength after completing their training program. Research clearly confirms the importance of resistance training for effectively reversing the muscle loss, metabolic slowdown, and strength decrement associated with the aging process.

There are many more health-related reasons why seniors should perform regular resistance exercise. As presented in the March 2002 issue of Fitness Management YMCA Quarterly, strength training can reduce the risk of cardiovascular disease, colon cancer, diabetes, osteoporosis, low back pain and depression (19).

Principles of Strength Training
Generally speaking, the guidelines for healthy senior strength exercisers are essentially the same as those for younger adults and youth. Basically, a well-designed strength training program for any age group consists of several exercises that address all of the major muscle groups. Studies with older adults have used as few as 5 exercises and as many as 15 exercises. For example, a landmark study with older women (13) incorporated only the leg press, leg extension, pulldown, back extension and abdominal curl exercises, whereas a classic study with senior golfers (17) included the leg extension, leg curl, hip adduction, hip abduction, leg press, chest cross, chest press, pullover, lateral raise, biceps curl, triceps extension, low back extension, abdominal curl, neck flexion, and neck extension exercises.

Sets
Most senior strength training studies have used a one, two or three set training protocol. Typically, programs with fewer exercises perform multiple sets, and programs with more exercises perform single sets. For example, participants in the older women study (13) performed 3 sets each of the 5 resistance exercises, whereas participants in the senior golfers study (17) performed one set each of the 15 resistance exercises. Participants in both programs completed 15 exercise sets per session, which represents a reasonable recommendation for most senior strength training protocols.

In a recent meta-analysis of several strength training studies, all but one showed no significant difference between performing single or multiple sets of resistance exercise (6). The researchers therefore concluded that training with one, two or three sets per exercise is equally effective for strength development and largely a matter of personal preference.

Based on the research protocols used with senior subjects and the comparative studies on exercise sets, a standard strength training session for older adults may include 8 to 24 sets of exercise. The following guidelines represent a sensible approach for training sets based on the number of exercises performed:

• 4 to 8 exercises………………………………………….... 2 to 3 sets each
• 8 to 12 exercises…………………………………..……... 1 to 2 sets each
• 12 to 16 exercises………………………………………... 1 set each