Happy New Year! Did you resolve to lose weight this year? Running burns a ton of calories so it should be a great way to melt off the pounds, right? Well, maybe not. Dr. Kyle Flack, a weight-loss researcher from the University of Kentucky, conducts studies on how the body responds to exercise and how much you really need to work out to work off those extra pounds, and it turns out you need to work out a lot more than the current recommendations suggest.

Dr. Flack was recently featured in a New York Times article on exercising to lose weight and he shares his research results and provides insights on why weight loss isn't as simple as burning more calories than you take in. He explains how body chemistry can seemingly work against us, thwarting significant weight loss, especially for fitter people, and why it's not uncommon for people to actually gain weight while training for a marathon.

Through his studies, Dr. Flack has found that people overcompensate for the calories they've burned pretty consistently, and he shares what the average calorie overcompensation amount is and how much exercise time is required to overcome it to really drop pounds. He also talks about how long it takes to make exercise a habit, he compares strength training to aerobic exercise for weight loss potential, and also reveals whether it's possible to build muscle and lose fat at the same time. If your goal is to lose or maintain your weight through your running, this is definitely a must-listen-to episode!

Kyle Flack grew up in a small town in Vermont where, as a 4-year starter on the varsity football team, earned All-State honors twice and won two state championships. He left to play college football at Ferrum College in Southwest Virginia, earning a BS in health sciences 4 years later. He continued his education at Virginia Tech in the Department of Human Nutrition, Foods, and Exercise, where he earned his PhD in 2014.

Upon beginning grad school, Kyle also turned over a new leaf in terms of his exercise routine, going from 280-pound power-lifting football player (who got winded walking upstairs) to a runner. He devoted an entire winter and spring to this newfound training, lost 40 pounds, and completed his first marathon, Vermont City Marathon in 2008.

From there he was addicted, running two marathons each year for the next 5 years throughout grad school and dropping another 30 pounds. Each marathon was a new learning experience, a new opportunity to get better, and always ended with the goal or running the next marathon faster!

After grad school, and after finally reaching that sub-3:30 goal (he did the Marshall University Marathon in 3:27) Kyle shifted his attention to triathlons, which he has been at since 2014. Kyle completed a Post-Doctoral research fellowship with the USDA in Grand Forks North Dakota from 2014 to 2017 and has since been an Assistant Professor at the University of Kentucky in the Department of Dietetics and Human Nutrition since 2017. Kyle is an RD (registered dietitian) and primarily focused on researching weight loss physiology, how exercise may affect eating behaviors, and how exercise can be more appropriately used for weight control.

Questions Kyle is asked:

4:52 You are a researcher at the University of Kentucky specializing in how exercise affects eating and weight loss. And you don't just study it, you used running to lose weight yourself. Can you share your experience?

7:27 You were already an athlete with football so it wasn't like you were obese or overweight and just wanted to lose weight by running?

7:58 Let's get into some weight loss science. It seems that weight loss should be easy. It's "calories in and calories out." What makes it more complicated than that?

10:00 When you lose weight, you're obviously lighter so there's less of you to move around. Is that correct?

10:30 Why isn't exercise generally effective for weight loss?

11:37 Overcompensating for calorie expenditure due to exercise is not entirely all our fault. This is not entirely a willpower issue or something like that. Our body's working against us. Is that correct?

14:28 What you're saying is when you go for a great run and you get all these endorphins flowing, you're feeling really good, the entire pan of brownies tastes even better, right?

15:15 Many athletes that I've coached have actually gained weight when they start training for a marathon. They are burning a ton of calories and for whatever reason instead of losing weight, they gain weight. How is that possible?

19:34 I did a calculator once to figure out how many calories I burned running a mile and it was something terrible like 56 calories, and I'm just like, "What! That's not fair." Why is our body doing this to us?

20:17 In a recent study you did, you and your team found that in order to lose fat, the participants in the study needed to burn 3000 extra calories per week. Can you talk about this study?

21:52 In your recent study, were the participants moving less in their normal lives when they weren't exercising? Were they slowing down?

23:27 The exercise you put the test participants through, was it just walking? Is that what you had them do?

23:51 Any other differences would you expect to find if you did the same study with athletes rather than obese, sedentary people?

25:01 Does the type of exercise matter? How about duration, frequency, or intensity?

26:44 The results of your study show frequency doesn't matter. That's good news for the weekend warriors, right?

27:19 You've also done some studies about the reinforcement value of exercise and I'd love to hear your thoughts on how we can make exercise a habit that we can stick to.

33:27 You're talking about a significant amount of exercise, five, six, seven hours a week for most people to get addicted to exercise?

34:11 One thing about exercise studies and nutrition studies, there's some inherent difficulties in studying human beings because we're not rats and you can't put us in cages. So what kind of limitations did you find in some of your studies? What are the challenges that you find in this kind of work?

39:36 Nutrition labels, they don't have to be perfectly accurate. I've heard that you can be 20% off on your nutrition label and it still be okay with the FDA. So calories in aren't always perfect, right?

40:12 What about strength training? How does that differ from cardio when it comes to weight loss, hunger, the afterburn? We hear that when you strength train, muscles take more energy to sustain than fat does so you're burning more just standing around if you have more muscle mass. Can you talk about that?

42:59 Can you gain muscle at the same time as lose fat? I've heard that that's not always the case. Is that possible?

44:18 What questions are still unsolved and what kind of research are you looking to do in the future?

Questions I ask everyone:

48:39 If you could go back and talk to yourself when you started running, what advice would you give?

49:46 What is the greatest gift running has given you?

50:19 Where can listeners connect with you?

Quotes by Kyle:

"If you lose weight, we would expect you to decrease your total energy expenditure, but what's really been found is that if you lose weight, you decrease it more than what we would anticipate."

"We need to exercise more to overcome that obligatory 1000-calorie-a-week compensatory response so we can actually see useful weight loss. So that 150-minutes-a-week recommendation that we hear actually isn't enough to overcome that compensatory response."

"With aerobic exercise, you can put someone on, 'You're going to exercise at this heart rate for 30 minutes,' and you can do that for everybody and they all have the same workout. But if you say, 'Okay, you're going to go to the gym and lift weights for an hour,' that's going to look completely different from one person to the next person in terms of muscle activation, what you're lifting, how heavy, how intense."

Take a Listen on Your Next Run

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Mentioned in this podcast:

kyle.flack@uky.edu

New York Times Article - Exercise for Weight Loss: Aim for 300 Minutes a Week

Runners Connect Winner's Circle Facebook Community

RunnersConnect Facebook page

https://runnersconnect.net/focus/

RunnersConnect Focus Classes

Use Promo Code RTTT for 20% off Sweaty Betty at www.sweatybetty.com/RTTT

Follow Kyle on:

Kyle Flack | Human Environmental Sciences (uky.edu)

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