Side Effects of Weightlifting

We always think of the short to mid term effects of weight lifting, and focus on the local area the muscles and there look.
But what about the broader effects, that regular weight lifting has on the body?

While there is a lack of research surrounding the topic, some studies have focused on the effects of weight training and the benefits that it has on your brain. One study, published in The Journal of The American Geriatrics Society, looked at how lifting weights affected the developing of age-related holes or lesions in our brains’ white matter, which is the material that connects and passes messages between different brain regions.

Naturally, these lesions will grow with age, and eventually the material deterioration could affect memory. The study used three groups to test the effect of exercise, and particularly weight training, on the lesions. Participants were broken up into three groups; the first group followed a once-weekly light program of upper and lower body weight training. The second group did the same, but completed the program twice a week. The final group, acting as a control, did stretching and balance exercises. All the participants did this for a year.

In the study, the control group and the participants who lifted once a week showed a significant increase in the number of white matter lesions, which in turn would lead to sustained brain and memory function. According to an article in The New York Times, the study suggests that lifting weights can have a positive impact on brain function, but according to Dr. Teresa Liu-Ambrose, “a minimum threshold of exercise needs to be achieved.”

Long-term weight training will improve your overall body coordination. This is especially important for the elderly who are more prone to injury due to losing balance. A study performed by James Judge appearing in the 1993 journal "Physical Therapy" showed that resistance training was able to improve the balance of elderly women. In addition to better coordination for injury prevention, the coordination improvements translate into sports related activities and can make you a better athlete.

Scientists have widely researched the acute effects of weight training on levels of certain important hormones. Although most studies confirm a rise in anabolic hormones (the muscle builders) and a reduction in catabolic hormones (the muscle destroyers) following strength training sessions (e.g. Craig et al., 1989; Kraemer et al., 1998), there are also some studies that didn’t find significant effects (e.g. McCal et al., 1999). Not only does the bulk of the researchers conclude that strength training boosts levels of anabolic hormones like testosterone, but it has also been shown to decrease catabolic hormones like cortisol (e.g. Staron et al., 1994). You know, cortisol, that notorious stress hormone that eats away your precious muscles when in high concentrations. So we know training probably has direct positive effect on the machinery of your body, but what about indirect longer term effects?

Although the direct effects of training are not convincing in all of the cases, the indirect effects are. The amount of fat and muscle you have appears to have great influence on your hormonal system. For instance, fat tissue makes your body resistant to insulin and leptin, and it produces aromatase (Cohen, 2001), an enzyme that converts testosterone into estrogen. Sounds nerdy, but what does it mean? It basically means that being fat puts your body in a state of storing future fat even easier! And lower testosterone (due to high conversion to estrogen) brings about many serious issues like muscle loss, loss of sex drive (for men and women) and low energy. Add up all these complications and the end result is being fat, becoming more fat and feeling like hell. Ouch! On the other hand, people with low body fat percentages show low conversion of testosterone to estrogen and higher sensitivity to leptin and insulin, making their bodies less prone to get out of shape by making more fat.

In my review of the scientific literature as I was writing this article, I came across some surprising studies. One of these was published in the Journal of Clinical Endocrinology & Metabolism and actually concluded weight training decreased bone mineral density in the subjects, who were premenopausal women.1 Another study showed weight training produced no significant increase in bone density.2 Fortunately, these were the exceptions rather than the rule, and the vast majority of research supports resistance training as a very effective means to increase bone density.3 (Still, I found those papers interesting and thought they were worth mentioning.)

Scientists from Tufts University, in a published paper4, said “over the past 10 years, nearly two dozen cross-sectional and longitudinal studies have shown a direct and positive relationship between the effects of resistance training and bone density. They also acknowledged that some studies do not support this relationship. However, study design and the specifics of the exercise may have influenced the results (and most likely did).

Another paper concluded that weight bearing exercise before puberty protected against osteoporosis later on by increasing peak bone mineral density.5

The list of supporting research goes on and on, and there are benefits of exercise beyond those which you can get from medicine or supplements.6 The degree of improvement in bone density varied with the study, but in the real-world, it doesn’t matter. It is enough to know that weight training increases bone density, which gives you one more reason to do what you absolutely should be doing anyway.

Weight lifting should be a regular part of your life, especially if your desk bound most of the day, and especially as you get older, and contrary to what people think, lifting generally does make you a hulk, which is a great thing for girls, it gives you the best figure you can have and also allows you to functionally use that strength and endurance to interact with your life.