For most women, adding resistance training to their fitness regime is the easiest way to reduce body fat and sculpt shapely muscles. Building muscle, however, requires protein, a dietary component that many simply aren’t getting enough of.
Not only does protein help to develop and strengthen muscle fibers, it also increases satiation, making it less likely that you’ll experience and give in to cravings for simple carbohydrates after your workout, thereby undermining your health and fitness goals.
I often recommend that my personal training clients consume protein shakes within an hour of their strength workouts; a simple way to get an extra serving of protein into their day. While many choose to supplement with whey or casein isolate powders, some have trouble digesting the milk-based proteins or, for other reasons, prefer to minimize the animal products in their diet.
Enter soy protein.
Like proteins derived from dairy and meat, soy protein contains the full complement of amino acids required by your body for all of its day-to-day functions. It’s low in fat and widely available. It contains more glutamine (a free radical-reducing antioxidant) and arginine (which speeds muscle recovery via improved blood flow) than either whey or casein. It has an intermediate digestion time (slower than whey and faster than casein), suggesting that when used in concert with one or both of the milk-based proteins, it may increase the length of the post-exercise recovery period during which muscle growth occurs. I’m all for getting the most out of my workouts!
At a recent academic conference, Dr. B. Rasmussen and colleagues (University of Texas, Medical Branch), presented the results of a preliminary study they conducted comparing the post-strength training benefits of consuming a soy/whey/casein protein mix relative to supplementing with whey alone.
Nineteen young adults (all male) were randomly assigned to one of the two treatments (whey and a combination of whey, casein and Solae™ SUPRO® isolated soy protein). Each participant was subjected to a high intensity leg-strengthening exercise and given their assigned protein supplement (20 g of protein) one hour after the workout was complete. Muscle protein synthesis was measured (by biopsy of a leg muscle) both before (as a baseline) and after the exercise bout (once 1-3 hours post exercise and a second time 3-5 hours post-exercise).
Despite the small number of participants in the study, results suggest an increase in post-exercise muscle protein synthesis by the soy/whey/casein combination group relative to the whey only participants. The authors concluded that the combination of slow, medium and long-digestion time proteins may lengthen the post-exercise recovery window, thereby allowing for potentially bigger strength gains than might be expected by using any one of the proteins by itself.
I want to know more; don’t you? I’d love to see this study extended over time to see if a longer post-exercise recovery window really results in improved strength in the gym. For example, assigning athletes to different protein supplementation regimes and measuring their 1RM on a standard strength exercise weekly for several months.
I’d also like to know whether the results are applicable to women; I work hard in the gym and if changing the type of protein I consume post-workout can give me better and faster results, I’m all for making a change.
Join me at a Twitter chat with Solae and FitFluential on Wednesday, May the 23rd, 8:00 pm CST (that’s 6 pm if you’re on the west coast). Follow my Tweets (fitknitchick_1) and the hashtag #SoyProtein for more information about soy and the benefits of including it in your post-exercise regime.
FitFluential LLC compensated me for this campaign. All opinions are my own.