Women, rev up your engines! You’re at the starting gate, your adrenaline’s pumping, and you’re ready to lose weight, gain lean muscle, and increase bone density. But you don’t need to do endless hours of cardiovascular exercise or take handfuls of pills. The fuel you need in your engine to win this race is as close as your local gym or maybe even your garage. Weight training, or resistance training, is the key that can unlock your potential for a healthy and strong body throughout your entire life. Stop those old perceptions about weight training making you big and bulky, or that weights are only for men or only for young people. Weight training has been proven to increase strength in women (1), assist in body fat loss and maintain or increase lean body mass (2), increase bone mineral density (3,4,5,6,7,8), and increase function in the elderly (9). Of course, if you’re a lean, mean, female machine, your mood will probably improve, as well as your self-confidence. So put your pedal to the metal, grab some iron, and let’s go!

Increase Muscle Size and Strength
Imagine living your life with more energy and strength to perform all of your daily tasks. You don’t need help carrying out the garbage, lifting the heavy boxes at work, moving the couch in the family room, or running around with the kids. This isn’t just a pipe dream. Weight training can help you perform all of these activities with ease. Women can increase their muscle size and strength if the training intensity and duration are sufficient, and can retain that strength throughout long periods of detraining (10). Another green light for weight training comes from The American College of Sports Medicine. This organization promotes and integrates scientific research, education, and practical applications of sports medicine and exercise science to maintain and enhance physical performance, fitness, health, and quality of life. They recommend moderate resistance training as an integral part of adult fitness programs (11). So don’t hesitate in the intersection – drive on through!

Looking Like a Girly-Man
But women shouldn’t worry that training with weights will make them look like female Arnold Schwarzeneggers, though. On average, a woman’s body structure is smaller than a man’s. Women also have lower levels of testosterone, the anabolic hormone that contributes to increased muscle mass, than men (12). Rather than getting big and bulky, weight training actually promotes changes in body composition that women find favorable, like decreased fat and increased toned musculature, without having to restrict calories (2,13). Although it sounds too good to be true, some women can stop the dieting and concentrate on weight training to change their body composition. For other women who may have higher body fat levels, some calorie restriction along with weight training may be necessary. Also, during periods of dieting, weight training can help reduce the loss of fat free mass that usually occurs with calorie restriction (14).
Osteoporosis Prevention
One practical application of Wolff’s Law, a classical and well-known theory on bone, is that weight-bearing physical activity like walking, jogging, and resistance training has a positive effect on bone mineral density by mechanically loading the skeleton. Research studies reinforce the idea of resistance exercise increasing the bone mineral density in pre-(3,4,5,6) and postmenopausal (7) and elderly women (8). With osteoporosis as a serious health threat to women, it makes sense to attempt to prevent it by making women’s bones as strong and as healthy as possible. Because peak bone mineral density is reached in late adolescence (15), prior to this time is ideal for women to start a resistance exercise program to possibly delay osteoporosis. However, you are never to old to start resistance training to increase bone mineralization. Bones that are strong can handle more stress and are less likely to fracture. The National Osteoporosis Foundation’s Physician’s Guide to Prevention and Treatment of Osteoporosis, 1998 (16) recommends regular weight-bearing and muscle-strengthening exercise both for osteoporosis prevention and overall health. The guide states that not only can this type of exercise improve agility, strength, and balance, thus reducing the risk of falls, but it may also yield a modest increase in bone density. Weight training is a valuable tool in the race against osteoporosis and fractures.

Safe and Smart
Grab your dumbbells, grandmas, and start curling! Resistance training in elderly women has shown to be safe and increase muscle size and strength (17). In addition, resistance exercise in the elderly population can improve function, which can lead to more independent living (9,18). The high levels of disability and falls in the elderly may be due to their low muscular strength (9,18). Because training with weights does increase muscle size and strength and increase bone density, older women who weight train can experience all of these benefits. Being stronger with larger muscles at an older age delays some of the natural aging processes like muscle loss, bone loss, a decreased metabolic rate, and decreased energy and activity levels (9,18). Practically speaking, older adults who weight train may have an easier time with their activities of daily living, may lengthen their years of independent living, and may experience less chronic diseases (9,18).

Lift Free
But don’t just go to the gym and spin your wheels. Don’t be afraid to lift free weights. Many times women rely on machine training only. A good routine will have you using free weights primarily and supplementing with machines. Research on the benefits of Nautilus machines on bone mineral density suggests that better results may have been obtained with free weights (19). Other research has shown that after 20 weeks of training on Universal-type machines, women improved their muscular strength and toned their bodies, yet did not increase bone mineral density (20). So, choose free weights whenever possible and try to follow exercise programs that are functional and mimic your daily activities.
Now, are all the women out there jumping in their cars and speeding to the nearest gym? With all of the benefits that weight training can offer, women should be racing to pump some iron. Women need to fuel their engines with some heavy machinery to make them strong, toned, happy, and live long, independent lives. Weight training is the answer to crossing the finish line in women’s race to stay healthy.

References:
1. Staron, RS, DL Karapondo, WJ Kraemer, et al. Skeletal muscle adaptations during early phase of heavy-resistance training in men and women. Journal of Applied Physiology. 76(3): 1247-1255, 1994.
2. Butts, NK, S Price. Effects of a 12-Week Weight Training Program on the Body Composition of Women Over 30 Years of Age. Journal of Strength and Conditioning Research. 8(4): 265-269, 1994.
3. Snow-Harter, C., ML Bouxsein, BT Lewis, et al. Effects of Resistance and Endurance Exercise on Bone Mineral Status of Young Women: A Randomized Exercise Intervention Trial. Journal of Bone and Mineral Research. 7(7): 761-769, 1992.
4. Dornemann, TM, RG McMurray, JB Renner, et al. Effects of High-Intensity Resistance Exercise on Bone Mineral Density and Muscle Strength of 40-50 year old women. Journal of Sports Medicine and Physical Fitness. 37: 246-51, 1997.
5. Lohman, T., S Going, R Pamenter, et al. 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 (7): 1015-1024, 1995.
6. Madsen, KL, WC Adams, MD Van Loan. Effects of Physical Activity, body Weight and Composition, and Muscular Strength on Bone Density in Young Women. Medicine & Science in Sports and Exercise. 30(1): 114-120, 1998.
7. Pruitt, LA, RD Jackson, RL Bartels, et al. Weight-Training Effects on Bone Mineral Density in Early Postmenopausal Women. Journal of Bone and Mineral Research. 7(2): 179-185, 1992.
8. Nelson, ME, MA Fiatarone, CM Morganti, et al. Effects of High-Intensity Strength Training on Multiple Risk Factors for Osteoporotic Fractures: A Randomized controlled Trial. Journal of the American Medical Association. 272: 1909-1914, 1995.
9. Evans, WJ. Effects of Exercise on Body Composition and Functional Capacity of the Elderly. The Journal of Gerontology. 50A: 147-150
10. Staron, RS, MJ Leonardi, DL Karapondo, et al. Strength and Skeletal Muscle Adaptations in Heavy-Resistance-Trained Women after Detraining and Retraining. Journal of Applied Physiology. 70 (2): 631-640, 1991.
11. American College of Sports Medicine’s Guidelines for Exercise Testing and Prescription. Fifth Edition. Eds. WL Kenney et al. Williams and Wilkins. Media, PA, 1995.
12. Designing Resistance Training Programs. Second Edition. SJ Fleck, WJ Kraemer. Human Kinetics. Champaign, IL, 1987.
13. Cullinen, K., M Caldwell. Weight Training Increases Fat-free Mass and Strength in Untrained Young Women. Journal of the American Dietetic Association. 98 (4): 414-418, 1998.
14. Geliebter, A., MM Maher, L Gerace, et al. Effects of Strength or Aerobic Training on Body Composition, Resting Metabolic Rate, and Peak Oxygen Consumption in Obese Dieting Subjects. American Journal of Clinical Nutrition. 66: 557-63, 1997.
15. Snow-Harter, C. K Marcus. Exercise and Bone Mineral Density, and Osteoporosis. Exercise and Sport Science Reviews. 19: 351-387, 1991.
16. National Osteoporosis Foundation Physician’s Guide To Prevention and Treatment of Osteoporosis, 1998. http://www.nof.org.
17. Charette, SL., L McEvoy, G Pyka. Muscle Hypertrophy Response to Resistance Training in Older Women. Journal of applied Physiology. 70(5): 1912-1916, 1991.
18. Evans, WJ. Exercise Training Guidelines for the Elderly. Medicine & Science in Sports and Exercise. 31(1): 12-17, 1999.
19. Gleeson, PB, EJ Protas, AD LeBlanc, et al. Effects of weight lifting on bone mineral density in premenopausal women. Journal of Bone and Mineral Research. 5(2): 153-158.
20. Chilibeck, PD, A Calder, DG Sale, et al. Twenty weeks of weight training increases lean tissue mass but not active bone mineral mass or lean density in healthy, active young women. Canadian Journal of Physiology and Pharmacology. 74: 1180-1185, 1996.