There is a new kind of fitness shoe on the market. It is a weighted shoe. Shoes used for jogging weigh less than a pound. Weighted fitness shoes, depending on the size, weigh 2.2 to 4 pounds each. Weighted shoes are worn only for walking (they should not be worn for jogging or other kinds of high impact, vigorous exercise). Investigators have found, however, that moderate exercise – i.e., walking – is equally effective as vigorous exercise in preventing coronary heart disease and some cancers, and in averting, or treating, insulin resistance and Type 2 diabetes.1 Why the weight? Studies show that adding a weight load to the lower part of the body at the ankles or feet substantially increases calorie expenditure. Walking in weighted shoes enables one, without changing his or her diet or level of activity, to lose weight. Adding weight to the feet also provides muscular resistance that strengthens and tones one's legs, buttocks, lower back, and abdominal muscles.
Investigators at Harvard carried out a prospective study of walking as compared with vigorous exercise in the prevention of coronary heart disease in 72,000 female nurses aged 40 to 65 years, published in the New England Journal of Medicine in 1999. Over an eight-year study period they found that sedentary women had substantially higher rates of coronary events (death and nonfatal heart attacks) than women who were active. The authors assessed the comparative roles of walking and vigorous exercise in the prevention of coronary events and found that the magnitude of risk reduction with vigorous exercise was no greater than that found in women who walked briskly three or more hours a week. Walking this amount each week reduced the risk of coronary events by 30 to 40 percent. Using statistically sophisticated multivariate relative-risk analyses, authors of this study estimate that more than one-third of coronary events among middle-aged women in the U.S. are attributable to physical inactivity.2
Children, adolescents, and men and women of all ages benefit from walking. A meta-analysis of childhood obesity published in Medicine & Science in Sports & Exercise (in 2002) found that the exercise program which was most effective in reducing body weight and percent body fat in this age group (age 517) was long walks, combined with repetition resistance exercise.3 Wearing weighted shoes on long walks further increases caloric expenditure, thereby helping to further reduce body weight and percent body fat, and they also provide a form of repetition muscular resistance while walking.
Americans today are becoming more sedentary and are experiencing an epidemic of obesity, insulin resistance (also known as metabolic syndrome), and Type 2 diabetes. Currently, 65 percent of US adults are overweight or obese, as measured by the Body Mass Index.4 Thirty-one percent are clinically obese. Americans weigh on average eight pounds more than they did fifteen years ago. The Surgeon General's report on overweight and obesity issued in 2000 says that less than one-third of US adults engage in the recommended amounts of physical activity and 40 percent do not engage in any leisure time physical activity.5 Type 2 diabetes, brought on by obesity and a sedentary lifestyle, afflicts 20 percent of the US population over age 65. Another twenty percent of the US population has developed insulin resistance (which turns into diabetes when the beta cells in the pancreas wear out making extra amounts of insulin trying to overcome the body's growing resistance to it). Worse than smoking, obesity combined with a sedentary lifestyle is the principle reason why two-thirds of people in this country die prematurely from cancer and cardiovascular disease.6
Another report by the U.S. Surgeon General on Physical Activity and Health7 notes that a growing body of scientific evidence indicates that physical inactivity is a major risk factor for cardiovascular disease (the most common cause of death in both men and women) and some cancers (colon cancer, in particular, and, according to some studies, breast and prostrate cancer). The report goes on to say that most Americans have little or no physical activity in their daily lives. It reviews prior public health recommendations and points out that they have evolved from emphasizing vigorous activity for cardiorespiratory fitness to now include "the option of moderate levels of activity for numerous health benefits." The report advises people of all ages "to include a minimum of 30 minutes of physical activity of moderate intensity (such as brisk walking) on most, if not all, days of the week." For people who can't find the time to do this and remain physically inactive, wearing weighted shoes is an alternative. In physically inactive people, wearing weighted shoes throughout the day while performing the activities of daily living (walking about the house, at work, doing household chores, preparing meals, shopping, walking back and forth to one's car in parking lots, etc.) can provide needed, and otherwise not obtained, aerobic exercise and leg muscle strengthening. People who follow the Surgeon General's recommendations on physical activity and take brisk walks three to four hours a week will achieve added benefits when they wear weighted shoes on their walks.
What is the metabolic effect of adding a few pounds of weight to one's feet? Soule and Goldman studied the energy cost of loads carried on the head, hands, or feet of young soldiers.8 They found that weights on the feet produces a six-fold increase in energy cost (caloric expenditure) compared with the same amount of weight carried on the torso, and a three-fold increase in energy cost compared with the same weight carried in the hands. A relatively small amount of weight added to the soles of the feet, therefore, has a disproportionately magnified effect on caloric expenditure.
A 185-lb. man walking three miles in an hour expends 300 kcal/hr (kcal = kilocalories, commonly referred to simply as calories). Studies show that the same walk wearing weighted shoes (3.1 lbs. each) generate a caloric expenditure of 600 kcal/hr.9 An individual who consumes 2,000 kcal of energy a day engaging in daily tasks, without exercise, will nevertheless increase her caloric expenditure by 25 percent by wearing weighted shoes, to 2,500 kcal a day. One pound of body fat has 3,500 kcal of stored energy. If a person carries out his or her daily tasks in a pair of weighted shoes, he or she will burn an extra 3,500 kcal a week – and thereby shed one pound of fat. Taking off one to two pounds a week is a healthy way to lose weight.
At any given time in the U.S., 33 to 40 percent of women and 20 to 24 percent of men are trying to lose weight. Dieting does not work. Most people regain two-thirds of the weight they lose within one year – and all of it back, and sometimes more, within five years. They lose weight by following a special kind of diet (low fat, high protein, or some other kind) and regain it when they resume their regular, "normal" eating habits. Wearing weighted shoes enables people to lose weight and keep it off.
The foundation of an exercise program is aerobic movement – walking, jogging, bicycle riding, swimming, rowing, dancing, skating, bouncing on a trampoline, jumping rope, cross-country skiing, etc. – but one also needs to do stretching exercises to increase flexibility, and weight training to tone and strengthen the muscles and increase muscle mass. A weight load in the soles of one's shoes works the muscles of the spine, abdominal muscles, gluteal (buttock) muscles, and the thigh and leg muscles simultaneously. The repetitive motion of walking in weighted shoes firms and tones these various muscle groups. Muscles burn calories more quickly than other tissues in the body, and having a well-toned muscle mass, which weighted shoes help provide, is an important factor in maintaining a healthful weight.
Wraparound ankle weights provide the same physiologic benefits as weighted shoes do, but they are much less comfortable and can place too much strain on the unsupported ankle and injure it. It is much better to place leg-bearing weights in the sole of a shoe. That way padding in the upper part of the shoe can support the ankle.
iWellness designs ergonomically engineered weighted fitness shoes called MetaTreksu2122.10 Multiple, small bars of steel laid transversely in the sole add 2.2 to 3.1 pounds of weight resistance, depending on the shoe size, to each foot. Like with regular fitness shoes, these shoes are flexible, support the foot's natural movements, and are comfortable to wear.11 They are durable, and the rubber outer sole is designed for good traction. The sole is laminated with shock absorbing Neopontex. The inner lining of the shoe contains charcoal for antibiosis and deodorization, along with nano silver to prevent and eradicate athlete's foot.
Comfortably fitting, weighted shoes are a new technology that enables busy people to "exercise" while they go about their daily activities. MetaTreks also come in black and, attractively designed, can be worn at work. Weighted shoes are made for low-impact exercise. You should not play tennis or jog in them. Walking in them, briskly or leisurely, is enough. As with any type of equipment, listen to your body. These shoes take time to get used to. They should be used moderately at first. Some people prefer to wear them on alternate days in order to give their muscles a rest. Once acclimated, however, they can be worn on a daily basis.
Weighted shoes are the next generation in fitness shoes. They enhance the benefits of walking, a low-impact, joint-sparing, moderate form of exercise that has been shown to have the same health benefits as more vigorous exercise. These benefits include a reduced risk of cardiovascular disease and cancer; and preventing insulin resistance and Type 2 diabetes, which is a consequence of obesity and physical inactivity. Exercise, enhanced by wearing weighted shoes, has also been shown to help lower high blood pressure, keep one's bones strong, prevent osteoporosis, and help relieve stress.
- Walker KZ, Piers LS, Putt RS, Jones JA, O’Dea, K. Effects of regular walking on cardiovascular risk factors and body composition in normoglycemic women and women with type 2 diabetes. Diabetes Care 1999; 22: 555-561.
- Manson JE, Hu FB, Rich-Edwards JW, Colditz GA, Stampfer MJ, Willett WC, Speizer FE, Hennekens CH. A prospective study of walking as compared with vigorous exercise in the prevention of coronary heart disease in women. N Engl J Med 1999; 341: 650-658
- LeMura, LM and Maziekas, MT. Factors that alter body fat, body mass, and fat-free mass in pediatric obesity. Med Sci Sports Exerc 2002; 34: 487-496.
- The Body Mass Index (BMI), used by doctors and insurers to measure obesity, is the relationship between a person’s height and weight, where BMI = W/H2 (W is weight in kilograms and H is height in meters). Individuals with a BMI 18.5 to 25 are normal weight (those less than 18.5 are underweight). People with a BMI greater than 25 are classified as overweight and those with a BMI over 30, as obese 30-34.9, moderately obese; 35-39.5, severely obese; and greater than 40, massively/morbidly obese. To calculate your BMI using weight in pounds and height in inches, multiply your weight by 703 and divide this by your height multiplied by itself-W (lbs.) x 703/H (in.) x H (in.) = BMI.
- U.S. Department of Health and Human Services. The Surgeon General’s Call to Action Prevent and Decrease Overweight and Obesity. Atlanta, Ga: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Center for Chronic Disease Prevention and Health Promotion, 2000. Stock number 017-001-00551-7.
- For more on this subject see Miller DW, Miller LL. Technologies for Maintaining Optimum Health and a Strong Immune System. On www.donaldmiller.com.
- U.S. Department of Health and Human Services. Physical Activity and Health: A Report of the Surgeon General. Atlanta, Ga: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Center for Chronic Disease Prevention and Health Promotion, 1996. Stock number 017-023-00196-5.
- Soule RG, Goldman RF. Energy cost of loads carried on the head, hands, or feet. J. Appl. Physiol. 1969; 27: 687-690.
- Studies done at Han-Lim University Laboratory of Shoes (in Korea) by Guak Chang-Su and at Osaka University School of Health and Sport Sciences (in Japan) by Mitsuhiko Masuhara.
- The company’s Website is www.iwellness.us.
- U.S. Patent No. 6,397498.
March 5, 2003