This is of special importance to women, since many experts believe that women runners are more vulnerable to bone loss and, hence, osteoporosis. In fact, some studies have shown that women who run long distances (as little as 5 miles a day) have lower bone density than women who just sit around doing nothing. Women with low bone density are prime targets for osteoporosis, which can lead to bone fractures and premature death.
More than a decade ago, the British Journal of Sports Medicine warned that "women who ran the most had the lowest bone density. Each extra 10 km run (6.21 miles) per week was linked to 1 to 2 percent lower bone density. Women who had more muscle lost less bone, but the most muscular women were not those who ran the most."
So, is it time to reconsider or give up your running program?
Ultimately, it's about balance. You need to incorporate strength training into your exercise program to bolster your peak bone-mass development.
Muscle mass is the most important variable that influences bone growth, and that growth is best achieved by regular progressive-resistance training. Unfortunately, many runners shy away from serious strength training and, therefore, unintentionally increase their risk for bone loss.
In all fairness, it's not just women runners who resist strength training - women in general are more inclined to skip the resistance training and opt instead for aerobic-type classes, erroneously believing that they're going to bulk up if they so much as touch a dumbbell.
Of course, nothing could be further from the truth. Ironically, the shapely body most women desire is best achieved by incorporating regular progressive strength training (which will shape the muscles and strengthen the bones), and not running (which shrinks your muscles and decreases bone density).
So, ladies, especially female runners, be sure to incorporate strength training into your fitness routine. If you've been avoiding the strength training, here are eight reasons why you need to pump it up:
1. You will lose body fat and increase lean tissue (muscle).
2. Weight training tones muscles, which looks great and raises your basal metabolism.
3. Weight training strengthens bones, reducing your risk of developing osteoporosis (weak and brittle bones).
4. Weight training can decrease body fat levels and reduce your risk of breast cancer.
5. Weight training can diminish the pain of osteoarthritis and reduce your risk of arthritis.
6. Weight training builds stronger connective tissues and increases joint stability, and reduces your risk of injury.
7. Weight training improves athletic performance.
8. Weight training will help you in your battle against stress and sadness.
Kimberly Garrison is a wellness coach and owner of One on One Ultimate Fitness in Philadelphia. Her column appears Wednesdays.