Fittness

Fitness

Walking Versus Vigorous Exercise

Moderate Activities²	MET Level
Lying quietly	1.0
Sitting, light activity	1.5
Mopping floors	3.5
Raking lawn	4.0
Mowing lawn, walking with power mower	4.5
Walking the dog	3.0
Volleyball, non-compet.	2.9
Calisthenics	4.0
Biking leisure pace	3.5
Golf, walking fast	4.4
Swimming slow	4.5
Walking 3 mph	3.3
Walking 4 mph	4.5

Vigorous Activities	6+ METs
Walking up hills	6.9
Climbing hills with 12 lb backpack	7.4
Walking 5 mph	8.0
Bicycling 10 mph	7.0
Bicycling 15 mph	10.0
Aerobic dancing	6.0
Jogging 12 min/mile	8.7
Rope skipping	12.0
Running 10 min/mile	10.2
Running 9 min/mile	11.2
Running 8 min/mile	12.5
Running 7 min/mile	14.5
Running 6 min/mile	16.3
Skating, roller blades	6.5
Skiing, water/ downhill	6.8
Squash, competitive	12.1
Surfing	6.0
Swimming, continuous	7.0
Tennis doubles	5.0
Tennis singles	6.5
METs are multiples of an individual's resting energy expenditure rate. For example: Running for an hour at a 9 min/mile pace is equivalent in energy expenditure (calories burned) to sitting and working for 7.5 hours.

Which is most helpful in preventing cardiovascular disease? New data just released from the large Women's Health Initiative study¹ (WHI) helps answer this question. This six year study includes 73,743 women. They compared the number of hours women walked daily and found that those who walked a half hour per day cut their risk of heart disease by 31%. Women who walked an hour a day or more cut their risk even further (42% reduction in risk) compared to non-walkers. Those who engaged in vigorous activity for 30+ minutes daily also lowered their risk by 42%, the same amount as those who walked an hour per day.

Both walking and vigorous activity are beneficial and seem to have a similar affect on risk. The advantage of the vigorous activity, however, is that it takes less time.

Walking + vigorous activity. Next the researchers looked at those women who did both, walking and vigorous activity. Those women who walked at least 2.5 hours per week and got an hour or more of vigorous exercise per week lowered their risk by nearly two-thirds (63%). While brisk walking has good cardio-protective affects, adding an hour per week of more vigorous activity such as running, bicycling, tennis or other active sports can have additional advantages.

This data agrees with the new recommendations by the Institute of Medicine, that most people need an hour of moderate activity daily for optimal benefit. Half an hour per day gives good benefit, but adding more time and a little vigorous activity appears to provide the best health advantage. When adding vigorous activity, be sure to gradually increase your intensity and time so you don't overdo. If you have any health problems, get your doctor's clearance before adding vigorous activity.

Here is the actual new guideline on fitness recommended by the Institute of Medicine². Physical activity and exercise promote health and vigor. Some benefits can be achieved with a minimum of 30 minutes of moderate intensity physical activity most days of the week. However, 30 minutes per day of regular activity is insufficient to maintain body weight in adults in the recommended body mass index ranges of 18.5 to 24.9 and achieve all the identified health benefits fully. Hence, to prevent weight gain as well as to accrue additional, weight-independent health benefits of physical activity, 60 minutes of daily moderate intensity physical activity is recommended.

For children, the physical activity recommendation is also 60 minutes or more of daily activity and exercise.

Reference

1. Manson JE et al. Walking compared with vigorous exercise for the prevention of cardiovascular events in women, New England Journal of Medicine Sep 5, 2002; 347:716-25
2. NAS, Institute of Medicine, Dietary Reference Intakes, National Academy Press, Chapter 12 -- Physical Activity, web released version, Sept. 5, 2002

Making Healthy Choices articles are written by Don Hall, DrPH, CHES president of LifeLong Health with contributions from associated health professionals. Content is general health information from evidence based research. It's purpose is not to treat disease or take the place of advice by your doctor but to promote healthy lifestyles. Persons with health problems should contact their physician for specific guidance.

Updated: 12/17/02