Strength Training for Women
A comprehensive look at why and how women should train for strength
By Patty S. Freedson , PhD
Only a decade ago exercise prescription typically consisted of cardiovascular conditioning and flexibility training. Little or no emphasis was placed on strength training, particularly for women. Today the emphasis has changed, and strength training is popular among both males and females. In almost every fitness facility, men and women of all ages are using weight machines and free weights with the help of their personal trainers. Even group exercise classes incorporate some form of resistance exercise into workout routines.
What is behind this shift? How has our approach to teaching and promoting fitness changed? First, we have recognized the importance of muscular strength as a piece of the fitness puzzle. It is no longer sufficient to simply exercise the heart and stretch our muscles. We must promote strength in those muscles as well. The effects of strength training include a highly toned body, enhanced strength and power, and improved sports performance. Second, there are significant health benefits associated with strength training. Stronger bones, reduced risk of osteoporosis, improved functional fitness and less susceptibility to injury are just a few.
Personal trainers can benefit from understanding the conditioning needs of their female clients of all ages. So let's begin the journey in examining strength training for women:
The first stop will examine gender differences in strength.
Second will be an analysis of research regarding the physiological effects of strength training, from both performance and health perspectives.
The third destination will present basic principles of weight training.
Fourth will be suggested program guidelines for strength training.
Finally, some of the common myths and misconceptions about women's strength training will be reviewed.
Gender Differences
Absolute strength, or the maximum amount of weight that can be lifted, is considerably higher for men than for women. In the upper body, the average woman is about 50 to 60 percent as strong as her male counterpart. In contrast, the gender difference in absolute strength in the lower body is smaller, with women exhibiting only about a 25 to 30 percent decrease in strength compared to men (Freedson 1994).
These regional differences between men and women in absolute strength raise an interesting question: Are there differences between women and men in muscle physiology between the upper and lower body? The answer is unequivocally no. The likely explanation is that women typically have participated in fewer upper-body resistance activities than men. The daily overload to a woman's upper body is much less. The lower body, specifically the legs, is naturally overloaded on a regular basis for locomotion purposes (otherwise known as walking). As women continue to add upper- and lower-body strength training to their regular fitness routines, this gender gap will likely be reduced.
When gender differences are examined relative to total muscle mass (pound for pound), women are similar to men in leg press strength (lower body) but about 20 to 40 percent weaker in arm curl strength and bench press strength (upper body). Thus, it appears that when training levels are similar for men and women, gender differences in absolute amount of muscle mass account for strength differences.
It is well known that strength and muscle mass decline with age. In one of the most comprehensive studies on age, gender effects and muscle strength, Lindle et al. (1997) studied 654 women and men (ages 20 to 93 years) as part of the Baltimore Longitudinal Study of Aging. The authors reported that strength begins to decline at age 40, and it decreases 8 to 10 percent per decade thereafter for both women and men.
The consequences of aging have been associated with negative health effects, including increased risks for falls, hip fractures and glucose intolerance as well as declines in bone mineral density (BMD). These negative outcomes have major economic and quality of life implications-all of which might be significantly reduced through strength training. The positive changes associated with systematic resistance exercise in older individuals are discussed later in this article.
Increasing muscle strength occurs by increasing muscle size and through improvements in how the nervous system communicates information to the muscles. It has been well established that muscles gain more mass as a result of changes in the size of the muscle fibers (hypertrophy), rather than through an increase in the number of muscle fibers (hyperplasia).
For the average female, increases in muscle size are relatively small. Consequently, the primary mechanism for strength improvements appears related to increased muscle fiber recruitment and improved coordination patterns of fiber recruitment. Research has shown that strength training causes relatively similar improvements in strength for women and men.
In a classic strength training study, Wilmore (1974) tested 73 college students (47 women and 26 men), who exercised two days a week for 10 weeks. Strength gains of 10.6 to 29.5 percent were reported for the women; for the men, 5 to 26 percent. Total muscle mass (amount of muscle hypertrophy) in the women increased 2.4 percent (measured by underwater weighing), which led the author to suggest that large gains in muscle size were not responsible for these young women's strength gains.
Many other health benefits have been documented for women who strength train:
In a study conducted at the University of Arizona (Lohman et al. 1995), researchers reported a 2 to 3 percent increase in lumbar spine (back) and femoral neck (hip) BMD after an 18-month strength training program among 22 women, ages 28 to 39 years.
The benefits of strength training extend to older women. In a study by Morganti et al., 20 women, all 60 years old, exercised twice a week for one year at 84 percent of one repetition maximum (RM). Performing an intense training regime, the women increased their strength in upper-body, lat pull-down by 77 percent, knee extension by 73.7 percent and double leg press by 35.1 percent. Although 40 to 50 percent of the strength gains were observed during the study's first three months, improvements in strength were observed over the program's entire 52 weeks.
Like their younger counterparts, older women also reaped the positive effects of strength training on BMD. In a study by Tufts University's Human Nutrition Research Center on Aging (Nelson et al. 1994), 20 women, ages 50 to 70 years, trained at high intensity two days a week for one year. The authors reported a one percent increase in femoral neck and lumbar spine BMD in the women, compared to the control group participants (no strength training), whose BMD decreased by 2 percent.
Resting blood pressure (RBP) levels also are impacted by strength training. Researchers at the University of Maryland (Martel et al. 1999) recently published a report on the effects of a six-month, three-day per week workout program on the RBP of 21 women and men (average age = 68 years). Strength increases alone were remarkable, averaging 20 percent for the upper body and 28 percent for the lower body. However, significant decreases in RBP also were reported. In fact, many participants shifted from a high-normal RBP category to a normal RBP level.
In another study by from the University of Maryland (Tracy et al. 1999), a 12 percent increase in leg muscle volume (measured using magnetic resonance imaging) was reported in 11 women, ages 65 to 73 years. Leg muscle quality, defined as the ratio of muscle strength to muscle volume, also increased by 16 percent. In other words, not only did the women's legs get stronger but the strength per unit volume of muscle (quality of muscle) improved dramatically as well.
Intra-abdominal obesity has been associated with a number of negative health outcomes, including cardiovascular disease and increased insulin resistance (greater risk of type II dia-betes). In a study of 14 women, all 67 years old, Treuth et al. (1995) reported strength increases of 51 percent for the upper body and 65 percent for the lower body following 16 weeks of strength training. Moreover, a 10 percent reduction in intra-abdominal fat (measured using computerized axial tomography) was observed.
Functional fitness, or the ability to carry out daily living activities, also improves in older women who strength train. In a study by Hunter et al. (1995), 14 women, ages 60 to 77 years, participated in a 16-week strength conditioning program and improved their strength by 52 percent. In addition, the women's self-selected walking speeds increased 18 percent; their arm muscle activity needed to carry a box of groceries decreased 36 percent; and their leg muscle activity while standing decreased 40 percent. Thus, following the resistence training program, the women were able to carry out daily living activities with less stress on their stronger muscles.
Even very old women benefit from strength training. In a study by Fiatarone et al. (1990), 10 women, ages 86 to 96 years and all residents of a nursing home, participated in an eight-week strength training program. These women increased their strength by 175 percent!
In summary, strength training in women has numerous performance and health-related benefits. One indirect advantage, particularly for older women, is the growing ease in which everyday activities can be performed. Some women simply avoid activities that involve carrying heavy objects and walking up stairs. Disengaging these activities, however, means inactive muscles became weaker and weaker, causing a further decline in functional fitness. Strength training can effectively break this cycle.
When women say they cannot do as much as they could in their youth, it's not necessarily because of age; rather, it's a function of doing fewer activities to overload their muscles.
Strength training used to be an activity mostly performed by men. Even after the fitness boom began in the 1980s, resistance training facilities mostly were frequented by men. One of the primary reasons for lack of participation among women was the proliferation of various myths and misconceptions about the effects of strength training on women. Following is a list of these beliefs and physiological rationales on why they're incorrect.
Strength Training Will Make My Muscles Large and Bulky. Strength training will result in a small increase in total muscle mass. However, large increases in muscle size will not result because female testosterone levels are low; this hormone appears necessary to elicit increases in protein synthesis (large muscle increases). Due to genetics and individual differences, some women will increase muscle mass more than others-but nowhere near muscle size increases observed in men.
I Cannot Increase Muscle Strength Through Weight Training as Much as a Man. Study after study have confirmed that strength training will result in strength gains at least as large as those observed in men. In some cases, relative strength gains in women were greater than those in men, because women's initial strength levels were lower, making the potential for improvements greater. (Some of the studies cited in the main article address this issue.)
My Strength Training Program Should Be Less Intense Than What's Recommended for a Man. There is absolutely no reason that the basic principles governing men's strength training programs cannot be used in designing women's programs. To wit: low repetitions and high resistance for increasing absolute strength and power; high repetitions and low resistance for muscle toning and muscle endurance.
Women Should Only Use Weight Machines and Perform Exercises at a Low Velocity. There's an incorrect notion that if women use free weights or perform exercises that involve explosive moves, their risk for injury is greater. There is absolutely no evidence of gender differences in injuries consequent to strength training. If women (and men) are taught proper mechanics for lifting, the risk of injury risk is reduced.
Older Women Should Not Participate in Strength Training Exercises. Older women must participate in activities designed to specifically strengthen all muscle groups if they want to maintain maximum health and lifestyle performance. Health benefits received from this type of exercise are numerous: reduced risk for osteoporosis, decreased risk of falls, sustained independence later in life and decreased risk of insulin resistance.
I Have to Join a Gym to Perform Strength Training Exercises. Inexpensive strength training devices are readily available and will likely cost less than a treadmill or bicycle ergometer. These include dumbbells, ankle weights, elastic bands, barbells and weight benches.
Basic Principles
Why do women strength train? There are several possible reasons for including this type of conditioning in one's overall fitness program. The most prevalent reasons are:
to improve appearance
to increase muscle strength and muscle power
to improve health
Various principles in women's strength training complement these reasons. Let's examine how women strength train based on the following four principles:
Overload Principle
Specificity Principle
We Are All Different Principle
Use It or Lose It Principle
To achieve maximum success with strength training, it is important to follow the overload principle, which refers to the volume of training. Overloading the muscles with more stress than usual will elicit the optimal adaptation response. Variations in overload are accomplished by manipulating the load being lifted, number of repetitions, sets of repetitions, rest intervals between sets and frequency of workouts per week.
For novices, two to three sets of 10 to12 repetitions are recommended. Following an initial habituation period (about two weeks), exercisers can advance to three sets of 10 to 12 reps and increase weight by two to five pounds. Most weight training workouts are performed two to three times per week on alternate days (for example, Monday and Wednesday, or Monday, Wednesday and Friday).
For advanced lifters, anywhere from 3 to 15 repetitions are recommended, depending on the aims of the weight training program. In addition, more frequent weight training workouts can be conducted, with alternate muscle groups being exercised on different days (for instance, strength training for the lower body on Monday and Wednesday; upper-body exercises on Tuesday and Thursday).
To increase strength, fewer repetitions (3 to 6) at higher resistances are recommended. Rest intervals between sets should be long enough so that maximal loads can be lifted; rest intervals between sets for the high repetition, low resistance workout can be shorter. To optimize gains in muscle endurance (capacity to sustain muscular movement) and for muscle toning, lower weights with more reps are recommended. The most important element of a good strength training program is sustaining it. Strength routines can become a regular part of almost any client's long-term exercise program.
Specificity Principle
The nature of the adaptation response consequent to strength training is determined by the specific type of exercise performed. For example, if one wants to improve cardiovascular fitness to enhance running performance, then endurance running workouts are the best way to achieve this goal. The same specificity principle holds for strength training.
If the primary goal is getting in shape for activities that primarily use the lower body, then the strength training program focus should involve mainly lower-body exercises. If, on the other hand, the general goal is for total body fitness and improved appearance, then the program should be structured with exercises for the upper and lower body.
We Are All Different Principle
If your aim is to attain Olympic-level performance standards, then being able to choose your own biological parents would have helped this quest. In other words, your genes are an important determinant of the training response.
Everyone can improve strength fitness by following a program conducted on a regular basis. However, the magnitude and nature of the response can be quite different among individuals- thus, the we are all different principle. Some women, for example, may increase their muscle mass more than others or improve strength more or attain it faster than others. Still, do not let clients become discouraged by this reality. Every woman has the potential to improve muscular strength with proper training and conditioning.
Use It or Lose It Principle
The overload principle dictates that for a training adaptation to occur, it is necessary to stress the system more than it is accustomed. If less stress is presented, the muscle will "detrain" and become weaker. The use it or lose it principle mandates that maintenance of strength fitness can only occur if one continues to train on a regular basis.
Still, some questions remain unanswered in the current research literature: How much strength training is necessary to sustain strength gains? Can an individual reduce strength training volume and still maintain strength? Until we have answers to these important questions, emphasis must be placed on maintaining a regular strength training program forever.
Program Guidelines
What exercise programs work best for women who strength train? Among the factors for trainers to consider are:
type of exercise equipment, and
program design.
Most clients will have questions related to these two areas.
" Should I use weight machines or free weights?" There is no right or wrong answer to this question, which is fairly common among exercisers training for strength. A savvy trainer might answer that question with a better one: "What type of equipment will help you to maintain your exercise program for a lifetime?"
If one is willing to learn how to use free weights in a safe manner, then free weights may be right. If it is easier to let machines dictate what muscle groups will be involved in an exercise, then a client must be willing to visit a gym regularly or invest $1,000 to $3,500 for a home-based system. Of course, a combination of the two is a possible alternative. (See "Weight Machines Versus Free Weights.")
Program Design
As most trainers know, every exercise routine should begin with a warm-up period that is both general and specific. General warm-up will include activities involving whole body exercises, such as calisthenics, stretching, stationary cycling and jogging in place. Specific warm-up will include exercises to be performed in the main program design, only using minimal amounts of weight. At the conclusion of every workout, participants should cool-down with some light stretching that focuses on all the muscle groups' range of motion.
For novice exercisers, select weights that can easily be lifted 10 times. Note: To avoid injury, it is better to start with weights that are too light rather than too heavy. One set of each exercise should be performed for the first few workouts.
Select exercises that work every major muscle group. A novice strength training program should include: bench press, lat pull-down, lateral raise, triceps extension, biceps curl, leg press, calf raise and abdominal curl. Additional upper-body exercises might include: upright row, bent row, reverse curl and bent arm pullover. Other lower-body exercises might include: leg flexion, leg extension and half or full squat. Additions or substitutions of lower-and upper-body exercises can be implemented after a few weeks of regular training. Following a familiarization period (3 to 6 workouts; 1 set of 10 reps for each exercise), build up to three sets of 10 reps for each exercise.
One program option is the DeLorme Method (1945), which provides a systematic strength training protocol. The method involves three sets of any given exercise:
Set 1 is performed at 50 percent of 10 RM.
Set 2 is done at 75 percent of 10 RM.
Set 3 is conducted at 100 percent of 10 RM.
The DeLorme Method requires clients, with the help of trainers, to determine the maximum amount of weight that can be lifted 10 times (cannot do an eleventh rep). While this system may seem cumbersome, it is good practice after the familiarization period. It allows clients to see their starting point and enables a month-to-month assessment of improvement (and, if necessary, to set new weights for the exercises). More advanced techniques can be implemented as clients progress.
Another option is to use TheRecommended Quantity and Quality of Exercise for Developing and Maintaining Cardiorespiratory and Muscular Fitness,and Flexibility in Healthy Adults ( ACSM, 1998). Some of the strength training recommendations are as follows:
for improving muscular strength and muscular endurance, eight to 12 reps per set
to maximize gains in strength and power, six to eight reps per set
for major muscle groups, eight to 10 reps per set
for program sessions, two to three days per week
for younger individuals, minimum of one set of eight to 12 reps (to fatigue)
for older individuals (50 years-plus), 10 to 15 reps per set
for athletes focusing on strength and power, one to three sets of six to 12 reps (to fatigue)
As many trainers know, the effects of strength training can be felt by clients after just a few workouts. Initially, these effects are built-in motivators. Over time, however, strength training can become boring, so it's important to offer clients variety. Change the routine order. Vary the sets, reps and loads. Have clients keep records so they can assess their improvements objectively. Adding strength training exercises to your female clients' fitness regimes will impact how they feel about themselves. Moreover, it enhances their health and well-being while improving the overall quality of their lives.
Strength Training Benefits for women
Improved strength and power
Increased strength of bones
Increased lean body mass
Increased functional fitness in older women
Improved glucose tolerance (lower risk for diabetes type II)
Improved balance and gait in very old women
Strength Training for Women, continued Weight Machines versus Free Weights Strengths Weaknesses Weight Machines safe
easy to use
work all major muscle groups
minimal skill required high cost
limited number of exercises
restricted movements Free Weights variety of exercises
mimic true movements
lower cost
develop skilled movement not as safe
require more skill
require spotters
References and Suggested Reading
American College of Sports Medicine. 1998. The recommended quantity and quality of exercise for developing and maintaining cardiorespiratory and muscular fitness, and flexibility in healthy adults. Position stand. Medicine & Science in Sports & Exercise, 30, 975-91.
DeLorme, T. L. 1945. Restoration of muscle power by heavy resistance exercise. Journal of Bone and Joint Surgery, 27, 645-67.
Fahey, T. D., & Hutchinson, G. 1992. Weight Training for Women. Mountain, CA: Mayfield Publishing.
Fiatarone, M. A., et al. 1990. High intensity strength training in nonagenarians: Effects on skeletal muscle. Journal of the American Medical Association, 263,3029-34.
Freedson, P. S. 1994. Muscular strength and endurance. In D. M. Costa & S. R. Guthrie (Eds.), Women and Sport (pp. 177-83). Champaign, IL: Human Kinetics.
Hunter, G. R., et al. 1995. The effects of strength conditioning on older women's ability to perform daily tasks. Journal of the American Geriatrics Society, 43, 7 5 6 - 6 0 .
Lindle, R. S. et al. 1997. Age and gender comparisons of muscle strength in 654 women and men aged 20- 93 years. Journal of Applied Physiology, 83, 1581-87.
Lohman, T., et al. 1995. Effects of resistance training on regional and total bone mineral density in premenopausal women: A randomized prospective study. Journal of Bone and Mineral Research, 10, 1015-24.
Martel, G. F., et al. 1999. Strength training normalizes resting blood pressure in 65- to 73-year old men and women with high normal blood pressure. Journal of the American Geriatrics Society, 47, 1215-21.
Morganti, C. M., et al. 1995. Strength improvements with 1 yr of progressive resistance training in older adults. Medicine & Science in Sports & Exercise, 27, 906-12.
Nelson, M. E., et al. 1994. Effects of high intensity strength training on multiple risk factors for osteo-porotic fractures: A randomized control trial. Journalof the American Medical Association, 272 1909-14.
Tracy, B. L., et al. 1999. Muscle quality. Effects of strength training in 65- to 75-yr old men and women. Journal of Applied Physiology, 86, 195-201.
Treuth, M. S., et al. 1995. Reduction in intra-abdominal adipose tissue after strength training in older women. Journal of Applied Physiology, 78, 1425-31.
Wilmore, J. H. 1974. Alterations in strength, body composition and anthropometric measurements consequent to a 10 week weight training program. Medicine and Science in Sports, 6, 133-8.
Patty S. Freedson, PhD, is graduate program director in the Exercise ScienceDepartment at the University of Massachusetts in Amherst. A member of the Life Fitness Academy Scientific andMedical Advisory Board, she can be contacted at
[email protected]