Scientists have plugged another gap in our understanding of hunger. And that’s a help in under-standing why some of us eat too much. Which can lead to obesity and all the ills it portends. It boils down to something called ‘the hunger hormone’…
One sure-fire way to keep yourself on a daily walking plan is to get
a dog who’ll ensure you get out at least once every day!
The hunger hormone is well known. It’s called ghrelin, and it circulates in two forms in our bodies. According to the preamble to a new study on hunger signals just published in the Journal of the Endocrine Society, ‘intense’ exercise is directly related to hunger sensations…
Another dimension
Ghrelin has been shown to have wide-ranging biological effects, the study report explains. I has a role in regulating energy balance, appetite, glucose homeostasis, immune function, sleep, and mem-ory. the study report explains.
The new findings constitutes whole other dimension to the long-known association between exer-cise and weight control. Not only does exercise burn Calories; we can now say with certainty that it also makes us feel less hungry.
What they did
Researchers set up an exercise platform designed to replicate different levels of exertion. The set-up also allowed them to take small, droplet-sized samples of circulating blood during exercise sessions. These were analysed for ghrelin levels.
Those levels were them compared with test subjects’ reports of how hungry they felt following ex-ercise at various intensity levels.
What they found
“We found that high intensity exercise suppressed ghrelin levels more than moderate intensity ex-ercise,” says study lead author Dr. Kara Anderson, of the University of Virginia. “In addition, we found that individuals felt ‘less hungry’ after high intensity exercise compared to [after] moderate intensity exercise.”
“We found that moderate intensity either did not change ghrelin levels or led to a net increase,” the study report noted. These findings suggest that exercise above the lactate threshold, “may be neces-sary to elicit a suppression in ghrelin.”
What is the ‘lactate threshold’?
“Your muscles do produce lots of lactic acid when you’re exercising, but that’s not the only activity that can create it,” the Cleveland Clinic explains. “Anything that makes your body use more oxygen than usual can cause your cells to produce lactic acid.”
Your lactic acid levels can rise significantly after such everyday activities as: A workout, doing yard-work or lugging heavy boxes while you’re helping a friend move.
The takeaway
“Exercise should be thought of as a ‘drug,’ where the ‘dose’ should be customized based on an indi-vidual’s personal goals,” Anderson proposes. “Our research suggests that high-intensity exercise may be important for appetite suppression, which can be particularly useful as part of a weight loss program.”
My take
Another key finding of the new study was that the hunger-supression effect of exercise was stronger in women than in men, at the same levels of exercise. Women, however started with higher levels of ghrelin before the their test sessions.
That, and the Cleveland Clinic findings about lactate production, suggest to me that even moderately intense exercise may benefit women significantly. I can personally attest to that. Even a brisk walk of 1 to 2 km before breakfast can make me noticably less hungry.
That regime was part of my daily routine some years back when I last instituted an active weight loss plan under which walking was my main activity. I lost more than 50 lb. of excess subcutaneous and so-called ‘belly’ fat in under 6 months.
And men may simply have to jack-up their walking speed a little to get the same benefits as women.
~ Maggie J.