Ask the Doctors

Dear Doctor: I'm 44, newly single, and have started lifting weights because I hear it can help with mood and confidence. Am I on the right track? Also, my brother insists I have to start eating a lot more protein if I want to see results in the mirror. Is this true?

Dear Reader: You're absolutely on the right track with adding exercise to your life. Numerous studies over the last few decades show a strong link between physical exertion and improved mental and emotional well-being. And while the so-called endorphin high of aerobic activities like running, cycling and gym-based exercise classes has gotten the most ink, there's a similar connection between resistance training (aka weight lifting) and improved mood.

In one study, healthy older adults who suffered from depression were placed on a two-month weight training program of three sessions per week. Among those who were assigned to the high-intensity group, which lifted heavier weights, testing showed that symptoms of depression were cut in half in more than 60 percent of participants. Among the low-intensity training group, close to 30 percent of participants saw similar results. What was really intriguing was that gains in muscle strength had a direct correlation to reduction in depression. The literature also shows a link between resistance training and a drop in levels of anxiety.

When it comes to the role of protein in building muscle by lifting weights, your brother is up on the latest developments. A recent review of existing research by scientists from several well-regarded institutions found that increasing protein intake beyond typical dietary needs resulted in a greater increase in muscle mass.

The scientists examined data from 49 studies with a total of 1,863 participants, both women and men. They focused on studies that lasted a minimum of six weeks and had a control group against which to compare results. They found that those weight lifters who boosted their protein intake not only increased muscle size and muscle mass more than the control group, but they also made measurable gains in the areas of strength and endurance. In fact, increased protein consumption resulted in an average 25 percent greater increase in muscle mass than the control groups, and a 10 percent gain in endurance. Also intriguing was the fact that this effect was particularly pronounced among participants who were older than 40.

So what's the magic protein number? According to the researchers' calculations, optimal protein consumption was 1.6 grams of protein per kilogram of body weight per day, or double the RDA of 0.8 gram of protein per kilogram of body weight. That means a 165-pound individual would need about 120 grams of protein per day. To put that into perspective, there are 6 grams of protein in an egg, about 40 in a chicken breast, and about 17 in a salmon fillet.

When it comes to all of this, both the exercise and the diet, we urge you (are any of our regular readers surprised?) to please check in with your family doctor before you get started.

(Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o Media Relations, UCLA Health, 924 Westwood Blvd., Suite 350, Los Angeles, CA, 90095. Owing to the volume of mail, personal replies cannot be provided.)

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