Can intense workouts curb your craving for chocolate, ice cream and other foods that keep foiling your weight-loss plans?
A new study finds that rats engaged in hard-core activity resist cues for high-fat food pellets. The discovery offers hope that humans who push themselves to exercise harder might also increase their ability to stick to their diets.
“When you exercise, several neurotransmitters are released, including endorphins, endocannabinoids and dopamine,” says Lindsay Ogden, personal trainer and small group training program experience manager at Life Time. “These are all ‘feel good’ hormones, which can help you avoid reaching for highly palatable foods to get the same feelings.”
What the study found
Researchers at Washington State University set out to test the ability of rats to resist what is known as the “incubation of craving.” This concept suggests that the longer we avoid something we crave, the more difficult it becomes to shut off the signals pushing us to give in to temptation.
Two groups of rats participated in the study. Both sets of rats initially fed on a steady diet of tasty, high-fat pellets that were dispensed after the rats pressed a lever.
The rats then were barred from eating the pellets for 30 days. During that time, one group of rats ran on a treadmill at high intensity, while the other did not exercise.
At the end of this period, all the rats were allowed to access levers that dispensed the pellets. However, the researchers had rigged the situation so that when the lever was activated, no pellet was distributed.
The rats that did not exercise pressed the lever again and again in hopes of getting a pellet, doing so far more often than the rats that had engaged in high-intensity exercise.
The researchers concluded that intense exercise appeared to fortify the rats’ willpower, helping them to avoid submitting to their craving for the pellets.
Can intense exercise help humans eat better?
Although the study results offer some hope for people struggling to eat better, there are limitations to the findings.
“This should go without saying, but people aren’t rats — especially when it comes to our energy demands and outputs,” Ogden says.
In addition, the study had a small sample size — 28 — and the rats only participated for 30 days, she adds.
Still, Odgen says there are good reasons to believe that humans who commit to a sustained exercise routine may be better able to keep their diets healthful and on track.
“I’ve also found when people make a healthy decision, like working out, it can help them make other healthy decisions throughout the day,” she says.
So, should humans work out more intensely in hopes of building other good habits?
Intense exercise can have health benefits for those who pursue it, Ogden says.
“Exercise drives results, because the body has to respond and adapt to stress,” she says. “Since high-intensity exercise causes more stress on the body, people can see adaptations very quickly.”
However, she adds that the most important benefits of high-intensity exercise can be obtained through moderate exercise. Such perks include improved vascular function, greater insulin sensitivity, and a reduction in cardiovascular disease risk factors.
A better exercise plan
Because of the risks that come with high-intensity training, Ogden suggests taking a more measured approach to exercise.
“The goal of the exercise is to support a better overall lifestyle and longevity,” she says. “Weight training and slow aerobic work support this more than high-intensity exercise.” She adds that this moderate approach creates a broader base of fitness and is more sustainable.
However, occasionally partaking in more intense workouts can have benefits, too. “It can add some variety to your training,” she says.
If you plan to try high-intensity workouts, take things slow to start, Ogden says.
“Going from low- or moderate-intensity workouts to intense exercise requires time and patience,” she says. “While you may be ready to jump in, the safest way to add more intensity is to do it in bite-size increments.”
Start by limiting yourself to one high-intensity workout and use the following approach to dipping your toes into high-intensity exercise, Ogden says:
- Step 1: Swap out one moderate-paced workout for more intense exercise – ideally, not longer than 10-20 minutes.
- Step 2: If you feel good and recover well, consider adding around 10 minutes to your single high-intensity session
- Step 3: If you continue to feel good during and recover well after high-intensity exercise, consider adding another high-intensity day of 10-20 minutes. “Be sure to space out your higher-intensity days,” Ogden says.
Take note of how you feel in the days after your intense workout. For example, do you:
- Feel achy, run down, unmotivated, anxious, on edge or fatigued?
- Experience restless sleep?
- Feel your energy levels fluctuating?
- Experience increased hunger?
“These are all signs that can point to working out too intensely for too long,” Ogden says.