Some people feel guilty if they don’t spend an hour exercising every day, but a new study from the University of Alabama at Birmingham (USA) should help these people stop feeling bad.
The study results suggest that working out with aerobics or weight training four times a week is healthier than working out six times a week.
The researchers started with a group of 72 sedentary women aged 60 to 74, and randomly split them into three exercise groups:
1) Exercise sessions twice per week: once aerobic, once weight training (1+1 group).
2) Exercise four times per week; twice aerobic, twice weights (2 +2 group).
3) Exercise six times per week; three times aerobic, three times weights (3 + 3).
The exercise was supervised and gradually intensified over the 16 weeks of the study. At 16 weeks, the women were jogging moderately or lifting weight for about 40 minutes for each session.
The women’s body composition, blood chemistry, maximal oxygen uptake (treadmill test) and resting metabolism were measured weekly as well as feelings of fatigue, depression, and vigor.
The researchers were also interested to see if there was a difference in the amount of energy the women expended in daily activities (other than the exercise periods). The women with higher energy expenditure would, for example, take the stairs more than the elevator, and be more likely to walk than drive.
At the end of the 16 weeks, all three groups of women lost body fat and gained endurance and strength, but, amazingly, the overall fitness improvements were the same in each of the three groups. Meaning the women who worked out twice a week had essentially the same improvements as the women who worked out six times weekly.
But there was a difference in daily calorie expenditures. The 2+2 women scored the best in how many calories they exerted daily. By the end of the study, they were exerting about 225 more calories daily than at the start of the study.
The 1 + 1 group improved also, and were burning almost 100 calories per day more after 16 weeks. The worst was the 3+3 women…at the end of the study, they were burning about 200 calories less than when the started!
It seems that exercise six times per week was too much, and lots of these women felt tired and were less likely to say, take the stairs rather than the elevator. The 3+3 group felt that exercise was taking too much time out of their schedule, and they became lazier in that they might opt for the elevator, and drive rather than walk.
In summary, the best performance overall was the 2+2 group, and close behind was 1+1. The woman who worked out six times per week didn’t get any additional benefit, and they felt more tired overall.
This is an interesting study, and it suggests that “less may be more”. However, it was only done in women over age 60, and until further studies, we don’t know if the results hold true for men and younger people too.
The bottom line: if you feel good working out six times a week, continue to do it, but if you want to only work out two or four times per week, that is fine too. Relax a bit; listen to your body,
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