I have been interested in what constitutes “too much of a good thing” with endurance exercise for some time. I first discussed it in my post “How Much Exercise Is Too Much?” and gave an update on it here. I recently came across an article in the peer-reviewed journal Nutrients that gave an interesting insight into the connection between endurance exercise and diet , specifically with regard to cardiovascular health. They reviewed disturbing evidence that those who do a lot of endurance exercise may be at increased risk for coronary artery disease, and commented “surprisingly, endurance athletes may have more advanced atherosclerosis and more myocardial damage, compared with sedentary individuals, particularly as they age”.
The authors then pointed out that endurance athletes tend to eat more than their sedentary counterparts, to fuel their activity. But this extra fuel is not necessarily healthy, especially if they are eating a typical modern diet like the Standard American Diet. Since many experts believe such a diet contains excessive amounts of animal protein and saturated fat, eating higher amounts of it may make matters worse. They then go on to argue that these exercisers would be better off eating a healthy plant-based diet which would lessen the load of animal foods that may contribute to arterial plaque formation. It would also reduce another contributor to coronary artery disease, inflammation.
I discovered this article in a video on Dr. Michael Greger’s website entitled “Why All Athletes Should Eat Plant-based Diets“. He reviewed the evidence that has been previously presented on the benefits of plant-based diets for athletes, most famously in the documentary “The Gamechangers“. But he also emphasized the new insight presented in ref .
Whether a plant-based diet is necessary to reduce the risk of coronary artery disease among aging athletes may be controversial. First, I always wince when I see “plant-based” instead of “whole-food plant-based”. I realize the latter is awkwardly long and it may be tempting to just say “plant-based” as an alternate, but this is a slippery slope. There are many unhealthy overprocessed foods that are still plant-based, such as candy and potato chips. Second, excess animal protein and saturated fat are not the only things wrong with typical modern diets, they also contain excessive amounts of sugar and other “bad carbs”. But I think it is clear that aging athletes should avoid the temptation of thinking they can eat whatever they want and they are protected by their exercise. Even for those who are not convinced it is necessary to follow a whole-foods plant-based diet, it would still be a good idea to follow healthy eating recommendations, such as Harvard’s Healthy Eating Plate.
In the famous novel Once A Runner, the lead character, a competitive collegiate runner, describes his eating by saying “if the furnace is hot enough it doesn’t matter what you put in it”. I think many athletes have this attitude, I certainly leaned in that direction when I was younger. I was happy I could get away with eating pretty much whatever I wanted as long as I exercised enough. But I believe this becomes more dangerous as we age.
- Barnard, N. et al, “Plant-Based Diets for Cardiovascular Safety and Performance in Endurance Sports”, Nutrients, Jan. 2019.