For Optimum Health: Balance Good Diet With Habitual Exercise

"We hypothesize that physical activity and diet quality are independently associated with lower mortality risk, and that high levels of physical activity, either in total moderate-to-vigorous physical activity or vigorous physical activity, cannot offset detrimental effects of poor-quality diet."

"Sensationalized headlines and misleading advertisements for exercise regimens to lure consumers into the idea of 'working out to eat whatever they want' have fuelled the circulation of the myth about 'exercise outrunning a bad diet'."

"Our study provided important evidence for health professionals that exercise does not fully compensate for a poor diet and that we should recommend and advocate for both an active lifestyle and a healthy diet."

"[The selection of target foods reflects recommendations from the American Heart Association] These food groups were selected as markers for overall diet quality because other important dietary components and/or nutrient groups, such as whole grains and dairy, were not measured during baseline assessment."

Research conclusion, BMG Sports Medicine

One of very few research projects taking on the pairing of exercise and diet slanted toward the conviction that vigorous exercise regimens are capable of reversing the effects of poor nutrition has reached the conclusion that whatever the type of exercise that is paired with a poor diet, in the final analysis makes little difference. While exercise is beneficial and its effects are credited with healthier outcomes, this is separate and apart from the issue of a diet low in nutritional quality and high in health-harmful substances.

An international team of scientific researchers out of Australia, the U.S., Italy and Norway made use of a large sample of British adults in research to determine what impact diet has on human health that could be counteracted by a good exercise regimen. The multinational research ream reviewed exercise and diets' independent impact and in turn their joint impact on all-cause mortality, cardiovascular disease and a number of cancers.

Self-reported health histories specific to diet and exercise habits of 346,627 study subjects between the ages of 40 and 69 were cross-referenced against data on local death records in the course of a decade. The purpose: to link cause of death to baseline health records gathered a decade earlier so that the impact of diet, exercise or a combination of both on mortality could be gauged. It was the very sparcity of such studies that motivated the study as well as curiosity whether vigorous exercise did in fact offer added protection against early death risk in comparison to more moderate exercise intensity.

Study subjects were fairly representative of most societies with 40.8 percent subscribing to no vigorous exercise weekly, 26.5 percent exercising fewer than 75 minutes of high-intensity workouts each week, and the remainder devoting over 75 minutes weekly to exercising vigorously. Concerning diet, 22 percent held a poor ranking, 53.4 percent a medium rating while 24.5 percent qualified as the healthiest in the diet category.

Separately reviewed, high levels of physical activity -- 211 to 450 minutes of moderate to vigorous weekly exercise along with a high-quality diet each was seen to have a positive influence on longevity. Study participants who excelled at both diet and exercise scored the lowest mortality risk. Leaving those who count on one healthy habit correcting the unhealthy one, extremely disappointed.

Slightly greater protection was provided with vigorous physical activity against cardiovascular disease as opposed to moderate-intensity exercise; only however, for those accumulating ten to 150 minutes of vigorous exercise a week. On the other hand, those who were credited with over 150 minutes a week failed to realize the same benefit boost. 

People with the healthiest diets saw a 14 percent lower risk of cancer mortality, representing a benefit that failed to extend to those with a low- or medium-quality diet. The research results give clarity to the reality that a love of exercise cannot mitigate the negative effects of a love of fast food.

"The study results are no surprise to me. Many people have come to see me in my private practice after suffering a heart attack when training for their fourth or fifth marathon, or right after doing a CrossFit exercise."

"When I do a comprehensive evaluation of their lifestyle, it is apparent that they thought their intense daily exercise regimen would make up for their poor, unbalanced diet, and it simply doesn’t." 

Michelle Routhenstein, cardiology dietitian