Fitness Files: Blog gives unfair analysis of low-intensity workouts
Zeke handed me the article with devilish glee. “You’ll be interested in this,” he said.
Was Zeke on a mission to silence Pam’s alarm clock, which shatters his sleep at 5:20 a.m. when she rises to meet me for a morning run?
Knowing Pam and I value slim waists, he figured he’d quash our early a.m. jogging habit with Dana Fullington’s article in The Denver Post titled, “Does cardio make you fat? Study says yes.”
Fullington says that 30 to 60 minutes “pounding away…sends your body a powerful signal to start storing fat instead of burning it.”
An Internet search did not turn up the European Journal of Applied Physiology study Fullington quotes, but many bloggers mentioned it.
Fullington says the stress created by longterm exercise suppresses “a very important hormone, T3 that’s produced by the thyroid to burn fat, [so] the body starts gaining and storing fat immediately.” She continues, “if you’re interested in losing weight, don’t jog…sprint!…work with weights…run with high intensity…!”
Forgive me, Ms Fullington, if I’m resistant to your “sprint” advice for the average person.
I asked Google, “Does long cardio cause weight gain?”
I found “Fat Facts by Len Kravitz, PhD, University of New Mexico. Dr. Kravitz asks, “What is the best exercise fat burning zone?”
Kravitz titles one section, “Is low intensity exercise better for fat burning?” To discover the answer Kravitz designed a trial where a 191 pound physically-fit male exercised for 30 minutes at 55% of his heart rate, a second session at 85% of maximum heart rate. His physically fit subject burned more calories at the higher intensity. So far, he’s in agreement with Ms. F.
However, he disagrees with Fullington, crediting long slower exercise: “Since most people can’t do ‘high intensity’ exercise on a daily basis due to potential overtraining …concerns, the best strategy is to integrate balance, long duration and high intensity workouts for optimal calorie burning”
Then Kravitz asks, “Does aerobic [lower intensity] exercise actually make you a better ‘fat burner?’”
1. Yes, due to increased oxygen delivery, fat burns more efficiently
2. Enhanced release of triglycerides
3. Augmented blood flow
4. Fat is more available for fuel
5. Increase in number and size of mitochondria or “fat burning furnace”
6. Speeds the breakdown of fatty acids
So Kravitz finds low-intensity training has myriad fat burning benefits. He does not mention weight gain effects of T3 hormone.
When I read Fullington’s warnings against long, slow cardio as “chewing up your precious calorie burning muscle,” making you eat more calories than you expend, and being the “ultimate weight-gain tool,” I wanted to say, “Hush.”
What if walkers and joggers read Fullington’s strong statements and stay home, fearing weight gain?
My interest in public health makes me uncomfortable with her alarming language, warning us away from moderate exercise. Steady daily workouts promote weight control, decrease heart disease, diabetes and some cancers.
So, sorry, Zeke. Pam and I will continue meeting in the early morning hours for a long casual run. We’ll gain all kinds of health benefits, awakening early to amble about, enjoying social sunrise jogs.
Newport Beach resident CARRIE LUGER SLAYBACK is a retired teacher who ran the Los Angeles Marathon at age 70, winning first place in her age group. Her blog is [email protected].