Science Proves Exercise Isn’t Enough

If you’ve ever wondered, “How important is diet to my goals”, today you will learn from six scientific studies that exercise alone is unfortunately not enough.

Why is it that you bust your ass training? Is it to better your health and wellness, improve performance, increase strength, add lean muscle, shed unwanted fat, rid yourself of aches and pains and just live better?  Odds are the answer is yes, which makes feeding your body the proper nutrition critical to any of those goals.

The vast majority of us are interested in improving body composition at lease on some level.  We may have a goal to lose body fat and add some calorie-burning lean muscle mass, a process known as re-composition. To achieve these goals, we obviously must have a varied, progressive strength and conditioning training program.

However, I’m here to share some sobering research with you to highlight the fact that exercise, in the absence of nutritional intervention, is shamefully lacking when it comes to producing the desired fat loss that you seek.

In other words, it doesn’t work.

When asked, “What’s the best exercise is for developing six-pack abs” renowned strength coach Mike Boyle will tell you, with a straight face and without hesitation, “Table push-aways.”

The fact of the matter is that you can’t out-train a crappy diet. It’s an old adage but it remains true. A recent study demonstrated shockingly embarrassing results after 16 weeks of a solid training program. In the study, researchers assigned overweight folks to either a control group — where they didn’t exercise at all — or an exercise group. The participants assigned to the exercise group trained for five total hours per week: three hours performing strength-training exercises with an Olympic weightlifting coach and two hours performing circuit training with a group exercise instructor. Throughout the course of the study, the scientists gathered data on body composition, as well as various other measures.

  • While the exercisers did get better results than the non-exercisers, the results were nothing short of embarrassing.
  • The control group gained 1 pound of lean mass, lost a ½ pound of body fat, and lost 0.5% body fat.
  • The exercise group gained 3 pounds of lean mass, lost 2 pounds of body fat, and lost 1.5% body fat.

While the control group sat on their rear ends, the exercise group trained intensely for 80 hours and lost only a few measly pounds to show for their effort.


Let’s look at another study that shows the same exact, pathetic results of exercise without nutritional intervention:

  • In a study conducted at the University of Oklahoma, researchers again had the exercising group perform five hours of training each week and compared the results with a non-exercising control group. In this study, the exercisers performed three hours of aerobic exercise and two hours of resistance training. At the end of 10 weeks, the exercising group had dropped a measly 1 ½ pounds of fat.


While there are handfuls more to show, let’s look at some research that demonstrates the promising perspective of what happens when we add nutritional intervention to a training program:

  • In a meta-analysis analyzing data from 25 years of research, scientists found that 15 weeks of combined dietary and exercise intervention produced a staggering 22-pound average weight loss that was also maintained by the subjects after one year.
  • In a 9-month study at the University of Pennsylvania, researchers separated subjects into one of three groups: 1. diet (D) intervention; 2. exercise (E) intervention; or 3. diet + exercise (DE) intervention. You guessed it: the DE group demonstrated a significantly greater weight loss than either the D or E groups. Notably, the D group also lost significantly more weight than the E group.
  • Researchers in Seattle performed a similar study to the one above but added a control (C) group and carried out the research for 12 months. In this study, the E group did lose slightly more weight than the C group, but the DE group blew those results out of the water: DE resulted in 3 ½ times greater weight loss than E alone.

The point of this is certainly not to, frustrate, or upset you. It might shake some sense into you if you’re the type who works out hard but refuses to eat better. You already know that a properly structured training program is part of the equation, and a significant one at that.

The point is to make it very clear that to optimize your efforts, your nutrition is going to play a huge role in your success.

I’d even argue it’s the most important part.

A good place to start is get an idea of what you’re eating everyday with a tracking app (MyFitness Pal, etc). From there, once you know what’s going into your body, you may be able to set some goals and develop a plan.

I’m here to help you reach your goals. If you have questions, fire away.


Caudwell P et al. Exercise alone is not enough: weight loss also needs a healthy (Mediterranean) diet? Public Health Nutr. 2009 Sep;12(9A):1663-6.

King NA et al. Beneficial effects of exercise: shifting the focus from body weight to other markers of health. Br J Sports Med. 2009 Dec;43(12):924-7.

Lockwood CM et al. Minimal nutrition intervention with high-protein/low-carbohydrate and low-fat, nutrient-dense food supplement improves body composition and exercise benefits in overweight adults: A randomized controlled trial. Nutr Metab (Lond). 2008; 5: 11.

Miller WC et al. A meta-analysis of the past 25 years of weight loss research using diet, exercise or diet plus exercise intervention. Int J Obes Relat Metab Disord. 1997 Oct;21(10):941-7.

Volpe SL et al. Effect of diet and exercise on body composition, energy intake and leptin levels in overweight women and men. J Am Coll Nutr. 2008 Apr;27(2):195-208.