Mythbusting | Weight Loss

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Mythbusting | Weight Loss

Renee J. Rogers, Ph.D., FACSM |  Feb. 13, 2020

blog_myth_weight lossWhen it comes to lifestyle weight loss there are lots of myths. The New Year brings more and more to the forefront as millions of Americans (approximately 45%) set resolutions to lose weight. In this blog, I bring forward my experience and the science driving how I coach clients and patients during their lifestyle weight loss journeys. Here are the top four weight loss myths I typically navigate.

Myth #1: The Need to Choose Diet Over Exercise: Weight Loss = 80% Diet + 20% Exercise

“Eat Less and Move More” is the general recommendation used to describe the likely more complicated relationship between lifestyle weight loss behaviors: diet and exercise. In reality, the key lies in trying to tip the energy balance scale. Optimally to achieve this, a combination of both reducing food intake and increasing activity is recommended. Yet, if it is simple math and diet is the driving force, it is understandable that many people choose to adopt weight loss strategies that focus on diet alone and drop the physical activity.  

As an exercise professional by training, I cannot help but steer clients and patients to incorporate exercise as a part of their weight loss strategy. This isn’t about bias (promise); science supports this rationale too. The two compelling reasons are centered around muscle loss and keeping the weight off.

Muscle Mass Loss:  When we lose body weight by cutting calories, we focus on losing fat mass but we are also losing muscle mass at the same time. Here’s where exercise come in. Studies show an attenuation, or slowing, of muscle mass loss whenever physical activity is part of the weight loss plan.

Keeping the Weight Off:  This is where exercise is our real partner. Once the weight is off, high levels of physical activity (upwards of 225-250 min/wk) seems to be important for helping keep the weight off – check out ACSM’s Position Stand. But why wait? Clients and patients should begin moving more and incorporating physical activity into their routines as early as possible during the weight loss journey. This can lead to a positive pattern of activity ahead of time.

Myth #2: I Exercised, So I Get To Eat More

Before believing this one, ask yourself – “what is the goal?” Let’s face it, some people definitely choose to use exercise as a way to burn more calories so they have “more room” for food later. In fact, many popular food tracking apps will automatically give you more calories for being active. However, this strategy is not generally recommended during weight loss.

If we are trying to create a caloric deficit with diet, we need to be accurate with calculating food intake. It’s not just reporting what we eat, but getting into the details that get to accurate caloric amounts. This means:

  • weighing and measuring every food portion
  • tracking all recipe ingredients
  • asking waiters at restaurants the composition of meals, plus more.

This is not easy and we are not always great at this. Studies on self-monitoring accuracy have shown that adults trying to lose weight largely underreport their food intake (by up to 47%). On the flip side, when it comes to exercise, activity trackers have been shown to be 27-93% inaccurate depending on brand, and research has shown that people overreport (without trackers) exercise by up to 51%.

Overestimating activity and underestimating dietary intake are not going to help tip the energy balance scale – so how can we be more accurate? Consider using exercise as the “buffer.” Instead of allowing yourself to eat more because you exercised, let exercise be the buffer for all the inaccuracies when it comes to recording dietary intake.

Myth #3: Burning Calories through Exercise means High-Intensity Workouts and Long Sessions at the Gym

This one gets at what I am going to classify as a negative thought when it comes to beginning an exercise regimen. Unfortunately, most people that I work with walk into a first session “believing” that exercise needs to “look like this” to be effective for weight loss.

Again, the reality is that moderate-to-vigorous intensity exercise is recommended, and we want to work towards burning as many calories as possible through accumulating physical activity minutes. Yet, achieving that volume can be done in a variety of ways (no one exercise mode is perfect) and more importantly the individual person needs to be considered.

  • What does the person like to do when it comes to activity?
  • Does the person have any injuries? Are they ready for high-intensity or long bouts of activity?
  • How much time can the person realistically commit to weekly gym workouts?
  • Does carrying extra body weight impact how a person’s body feels exercising or their comfort level with certain activities?
  • Can the person get other activity minutes in outside of the gym?

Research shows that it is not just about the intense workout that happens in the gym. A study of 260 adults participating in a weight management program found that after 18-months, those that had greater amounts of light-intensity activity beyond structured moderate-vigorous exercise lost more weight.

All physical activity burns calories. More intensity equals greater caloric burn, but more overall volume, even at lower intensities and durations can add up too. Consider building physical activity into the entire lifestyle not just at the gym, to maximize overall volume. Activity programming should be designed to balance burning calories with individualized strategies that keep the person “moving more and sitting less” through their entire day. Even a one-minute activity break can be a move in the right direction. The new Physical Activity Guidelines for Americans support the approach that “every minute counts.”

Myth #4: Everything has to Change Immediately

Okay, this whole blog I have been encouraging physical activity in combination with reducing intake for weight loss. However, I am not naive to how difficult that can actually be. It can be a lot on the body and the mind to start doing high volumes of activity and completely changing diet patterns all at one time. This may be the reason why many people quit weight loss strategies early. The return on their investment (time, energy, commitment) is often bigger than the changes they initially see on the scale. We often don’t realize how much work it will take until we get started. But don’t fret, here are my favorite strategies based upon many of the lifestyle weight loss projects that I have been involved with.

Stacking Behaviors: Everyone is different, but we often see that people prefer to start by conquering one weight loss behavior before the other. I like to call this the trigger behavior – success in one area can fuel motivation and self-efficacy in another. This can be different for every person, so determining what the person feels more comfortable starting with (diet or exercise) may be a positive strategy. The end goal should be eventual participation in both behaviors. In our weight loss programs, we typically recommend starting with the diet and slowing overlaying activity.   

Start Low and Go Slow: This goes for both exercise and dietary strategies. Extreme changes are often not fun and not sustainable. Expecting perfection can be followed by frustration. We have to celebrate the small successes around developing positive patterns like taking a 10-minute walk each day at lunch, or meal prepping for a healthy dinner for an entire week. These patterns early on may be more important than doing the highest calorie-burning workout, or eating the perfect number of calories in a day. These patterns may be building a foundation for maintaining positive eating and activity habits for the long haul.

Make a Ramp Up Plan: We start low and go slow, but we should also try to set short term goals that strategically introduce the next positive layer of weight loss behavior. We love doing this with physical activity minutes. For example, during the first two weeks while we are targeting diet, the goal may be 100 minutes of activity spread across five to seven days (14-20 min/day). Then, every two weeks, activity minutes climb by 25 min/wk. The first bump-up is 125 minutes (17-25 min/day). With this strategy, by weeks 11 and 12, a person can be up to 225 min/wk and meeting the recommendation for weight loss maintenance. Ramp up planning can work well for both the dietary and activity goal setting.

Renee Rogers photoRenee J. Rogers, Ph.D., FACSM, is an Associate Professor in the Department of Health and Physical Activity and the Director, Health and Wellness Programming and Moving Health with Media Core in the Healthy Lifestyle Institute at the University of Pittsburgh.