Bracko,, Michael R. Ed.D., FACSM
Michael R. Bracko, Ed.D., FACSM, is an exercise physiologist and director of the Institute for Hockey Research and the Occupational Performance Institute in Calgary, Canada. He is an associate editor for ACSM's Health & Fitness Journal® and works in three areas: 1) sports physiology, where he conducts research on the performance characteristics of female ice hockey players, teaches high performance skating, and serves as physiologist for the University of Alberta Women's Hockey Team and the U.S. Deaf Olympic Men's Ice Hockey Team; 2) the health and fitness industry, by contributing to Impact Fitness Magazine in Calgary and by presenting at health and fitness meetings such as the ACSM's Health & Fitness Summit & Exhibition; and 3) as an occupational physiologist, in the areas of injury prevention, ergonomics, workstation stretching, and prework warm-up.
Note from Editor-in-Chief Ed Howley: This new column highlights a variety of current research studies of high interest to the readership. I want to thank Mike Bracko for taking on the task and ask the readers to send suggestions about what you would like to see in future issues of the Journal.
Comparison of 10,000 Steps with 30 Minutes of Walking
In this study the researchers compared the steps accumulated by women who were told to walk 10,000 steps per day with women told to take a brisk 30-minute walk on most, preferably all, days per week. Fifty-eight sedentary women (mean age 45 years) were assigned to either a "10,000 steps" group or a "30-minute" group.
After a two-week activity assessment where subjects wore a sealed pedometer, those averaging more than 7,000 steps per day (actual was 5,760 steps per day) were randomly assigned to the "10,000 steps" group or the "30-minute" group for a four-week intervention. All subjects wore a sealed pedometer, and the "10,000 steps" group wore a second pedometer to count their daily steps.
The results indicate that the "10,000 steps" group walked significantly more than the "30-minute" group. The "10,000 steps" group walked 10,159 steps per day compared with 8,270 steps per day for the "30-minute" group. The "10,000 steps" group averaged 11,775 steps on the days they achieved their 10,000 steps, and 7,780 steps on the days when their target was not achieved. The "30-minute" group averaged 9,505 steps on the days that a 30-minute walk occurred, and 5,597 steps on the days when no walk occurred.
The authors conclude that the women who were told specifically to achieve 10,000 steps per day walked more than the women who were told to walk for 30 minutes on most days. Interestingly, on the days that the "30-minute" group achieved their goal, their average step count was near 10,000 steps (1).
More McDonald's Restaurants in Poor Neighborhoods
This study was done in the United Kingdom where researchers sought to determine whether there were more McDonald's restaurants in "deprived" (poor) neighborhoods in Scotland, England, and the two countries combined. The researchers collected data on population, deprivation (socioeconomic status), and the location of McDonald's restaurants for 38,987 small areas in Scotland and England. They measured the number of restaurants per 1,000 people for each area.
The results show a significantly positive association between neighborhood deprivation and the mean number of McDonald's per 1,000 people for Scotland, England, and both countries combined. The authors suggest that these data may support environmental explanations for the high prevalence of obesity in poor neighborhoods (2).
Stretching Decreases Jumping Ability and Agility
A very D. Faigenbaum, Ed.D., FACSM, and colleagues investigated the effect of static stretching versus dynamic exercise on vertical jump, long jump, shuttle run, and v-sit flexibility. Twenty-seven girls and 33 boys randomly performed three different warm-up protocols: 1) 5 minutes of walking and static stretching, 2) 10 minutes of dynamic exercises including hopping, skipping, and jumping, and 3) 10 minutes of dynamic exercises including three drop jumps from a fifteen cm box. The subjects were tested two minutes after the warm-up exercises.
The results showed that vertical jump height and long jump distance were significantly lower and shorter after static stretching compared with the two dynamic warm-ups. Shuttle run time was slower after static stretching compared to the dynamic warm-ups. The dynamic warm-up with drop jumps resulted in faster shuttle run times compared to the warm-up without drop jumps. There were no differences in the warm-up protocols on the v-sit flexibility.
The authors concluded that a practical alternative to static stretching is to have kids perform dynamic movements as a warm-up. This is especially important when the activities require performance with high power outputs (3).
Michele Olson, Ph.D., FACSM, from Auburn University presented this research at the 2005 ACSM's Health & Fitness Summit & Exhibition in Las Vegas. She investigated the number of calories burned when performing Pilates. Specifically, she wanted to determine the calories burned during: 1) Basic/Beginner, 2) Intermediate, and 3) Advanced Pilates Mat Workouts. She had the subjects perform all three workouts in random order and measured the amount of oxygen consumption (and calories burned) during each workout.
The results indicate that the Basic/Beginner work-out burned 4 calories per minute, and 140 calories in 40 minutes, which is considered low-to-moderate intensity and equivalent to a stretching workout. The Intermediate workout burned 6 calories per minute, and 240 calories in 40 minutes, which is considered a moderate-intensity workout and equivalent to stepping up and down on a four-inch step. The Advanced workout burned 7.5 calories per minute, and 300 calories in 40 minutes, which is considered moderate- to-high intensity and is equivalent to speed walking at 4.5 mph.
Other findings of the study include: men burn more calories than women, and the calories burned varied within a workout depending on exercises used- side bend, jack-knife, and boomerang burned more calories than seated twist, "hundred," and leg circle (4).
Exercise Treatment for Depression
The authors of this study investigated whether exercise was a good treatment for mild to moderate depression and if there was a dose-response relationship between exercise and the reduction of depression. Eighty adults between the ages of 20 and 45 years with mild to moderate depression were randomly assigned to one of four aerobic exercise treatments: 1) Low Dose-3 days/week; 2) Low Dose-5 days/week; 3) Public Health Dose-3 days/week; 4) Public Health Dose-5 days/week; and a placebo group, who performed 3 days/week of stretching exercises.
The dose of exercise was determined by using the ACSM exercise prescription guidelines and the Consensus Public Health Recommendations for Physical Activity. The "Low Dose" was 7 kcal/kg/week and the "Public Health Dose" was 17.5 kcal/kg/week.
The primary result was Hamilton Rating Scale for Depression scores were reduced 47% from baseline for the "Public Health Dose," compared with 30% for "Low Dose," and 29% for placebo. There were no differences between 3 and 5 days/week of exercise. The authors conclude that aerobic exercise according to public health recommendations is an effective treatment for mild to moderate depression (5).
1. Hultquist, C.N., C. Albright, and D.L. Thompson. Comparison of walking recommendations in previously inactive women. Medicine & Science in Sports & Exercise®
2. Cummins, S.C.J., L. McKay, and S. MacIntyre. McDonald's restaurants and neighborhood deprivation in Scotland and England. American Journal of Preventive Medicine
3. Faigenbaum, A.D., M. Bellucci, A. Bernieri, et al. Acute effects of pre-event static stretching and dynamic exercise on fitness performance in children. Medicine & Science in Sports & Exercise®
4. Olson, M. "Pilates: A Man or an Exercise Method, Lessons From the Lab." American College of Sports Medicine's Health & Fitness Summit & Exhibition, April 2005, Las Vegas, NV.
5. Dunn, A.L., M.H. Trivedi, J.B. Kampert, et al. Exercise treatment for depression:Efficacy and dose response. American Journal of Preventive Medicine