The running/weight loss illusion

Many new runners are puzzled as to why the excess weight is not falling off their bodies. Here are some reasons why.
Aug. 20, 2010 | By: Alexis Williams

Did you think when you started running the pounds would drop off? Were you stunned when your scale didn’t budge, despite increasing distance?  While running can be an effective weight loss tool, for many runners this isn’t the reality.

Before I go any further, let’s not forget about the plethora of other health benefits of running or walking that can positively impact your weight:

• Managing stress can lead to less emotional binge eating, a big problem for many people who struggle with their weight.
• The many health-related benefits of exercise include prevention and treatment of major diseases like diabetes, osteoporosis, heart disease and arthritis.
• Running and walking groups provide a social outlet, which is also beneficial to your health and well being.

So what’s the downside? Why aren’t all runners lean and light?  A recent study attracted media attention when the authors implied exercise is ineffective for losing weight. While it had many in the fitness community scratching their heads, there were a few key points we can take away from this study.

Running burns calories; there is no debate about that. For example, a 150 lb runner will burn approximately 600 calories in a one-hour run. If you were to burn this many calories each day and keep their diet the same, you would lose approximately 1 pound per week. The catch is that keeping your diet the same is difficult when you train this much. So how can runners reap the weight loss rewards? It all comes down to calories in and calories out.

To lose weight and body fat, the body must be in a calorie deficit. One pound is equal to approximately 3,500 calories, so a deficit of 500 calories per day equals one pound per week. The safe, healthy weight loss range is up to two pounds per week. Beyond this level, you risk losing muscle and the likelihood you’ll maintain weight loss becomes scarce.

Exercise can stimulate the appetite. While you may have heard that “exercise is an appetite suppressant,” most people deny this and there isn’t much science to support the notion. While it’s true that intense exercise can temporarily blunt your appetite, it usually catches up to you (with gusto) after you’ve cooled down. The caloric deficit created in a training session is easy to undo when hunger pangs hit.  For example, a fancy coffee beverage from a favourite post-run meeting spot can do the damage quickly, obliterating any calories burned in an easy 5 km run.

Another challenge runners face is that our culture prompts us to use food to reward ourselves. Growing up, do you ever recall having ice cream after your little league games? While this is normal and can be part of a healthy childhood, the associations we make with food and rewards often stay with us. Have you ever found yourself thinking, “I’ll have another slice, I ran today” and digging in?

A recent study highlighted physiological reasons related to hormones that actually drive our bodies to crave replacement of expended calories (especially in females). In some ways we’re fighting nature when we try to create a calorie deficit.  Physical exhaustion and fatigue can also make us crave and feel hungry.

So can we change the running weight loss myth into a reality? The key is to trick your body into feeling more full, while gradually reducing your calorie intake. The Volumetrics diet by Dr. Barbara Rolls has sound evidence-based advice to aid in achieving a calorie deficit. The concept behind this approach to nutrition is to fill up on nutrient dense but energy light foods like fresh fruits and vegetables while limiting calorie dense foods like high-fat and highly-refined carbohydrate foods. Other studies have shown lean protein to be important for maintaining satiety and minimizing muscle losses while cutting back on calories. Many runners want to jump on the low carb bandwagon for quick results, but reducing carbohydrates too drastically will make running difficult and limit performance. While reducing your portions is reasonable, don’t eliminate carbs completely. A good guideline is to aim for 1/4 to 1/3 of your plate being starchy carbohydrate foods and choosing less processed options (whole-grain pasta, brown rice, quinoa, sweet potatoes etc.). I don’t recommend reducing carbohydrate intake below 3g/kg for anyone training three times per week or more.

When it comes to weight loss, slow is always better. A modest calorie deficit is easier to maintain and even if it makes your goal take longer, it’s worth it. Just slashing 200 to 300 calories per day will help you get off almost 20 to 30 pounds a year.  While this isn’t the quick fix you may want, it’s better for your health, your running performance and your metabolism. It will also be more effective with sustainable behaviours. Slashing 200 to 300 calories is simply changing from two double-double coffees a day to black coffee or coffee with a single milk, or cutting out the bowl of chips at night. Although it sounds easy, it takes dedication, accountability and cognitive awareness to maintain any behaviour change.