In a study published in the Journal of Clinical Investigation, researchers from the University of Copenhagen analysed the diverse impacts of different forms of training. In an experiment, 10 healthy men were divided into two groups who did both forms of training once a week for 60 minutes. The cardio session involved cycling at a level of 70 percent maximum oxygen intake, while the strength training consisted of five functional exercises repeated 10 times.
The participants then had their blood tested over a period of four hours to measure blood sugar, lactic acid, various hormones and bile acid in the body. They discovered that sweating it out on exercise bike caused three times the amount of the hormone FGF21 to be released by the body, compared to lifting weights. FGF21, or fibroblast growth factor 21, is a major metabolic regulator that plays a role in controlling glucose levels, insulin sensitivity and ketogenesis.
“Endurance training on a bicycle has such a marked effect on the metabolic hormone that we know ought to take a closer look at whether this regulation of FGF21 is directly related to the health-improving effects of cardio exercise,” said the study’s co-author Christoffer Clemmensen.
“FGF21's potential as a drug against diabetes, obesity and similar metabolic disorders is currently being tested, so the fact that we are able to increase the production ourselves through training is interesting.”
Your metabolic rate is depends on a range of factors including hormones, sleep, diet, sex, genetics and age. Increasing your metabolism can be beneficial, as it boosts the amount of calories you burn at rest, which can help promote weight loss.
“HIIT is always going to be the stronger, most effective opponent to burn fat and build lean muscles because of its after-burn effect,” Tiffiny Hall told Women’s Health. “I’m talking the EPOC (Exercise Post Oxygen Consumption) response... It means you keep burning off calories and energy even when you’re back at your desk staring at a spreadsheet, long after your last shine session. It means all of that huffing and puffing and changing and starting and stopping during your workout kicks your metabolism into high gear for hours after you finish exercising.”
What about the old adage “muscle burns more than fat”? Research shows that roughly half a kilo of muscle burns between seven to 10 calories per day while the equivalent of fat only burns two to three. Not a huge difference in the grand scheme of things.
But by no means does this mean you should ditch the dumbbells. A huge range of research promotes the benefits of resistance training which include the prevention or control of chronic conditions like diabetes, heart disease, arthritis, back pain, depression and obesity, reducing risk of cancer, reducing risk of osteoporosis, boosting mental health and improving sleep.
“Gaining muscle through resistance exercise means you can do more. You can work out harder and hike steeper trails,” sports dietitian Marie Spano told SELF. “This will lead to an increase in calories burned. Now, that’s significant.”
“It’s not about doing one OR the other, it’s about one complimenting the other to bring you results,” Tiffiny adds.
So like everything in life, balance is key. Ensure your weekly workout routine includes a bit of HIIT, some weights and a little stretching to reap the best possible benefits for your health.