Remember when your mom would snap "No snacks!" before mealtime because it would "ruin" your appetite? It stands to reason that if you eat a rich snack before a meal, you either won't eat your meal, replacing nutritious meal calories with empty snack calories, or you will gobble down both the snack and the meal.
But what if the idea of "snack" were redefined? What if a snack right before meals could help you regulate your blood sugar and prevent cardiovascular disease? You'd stock up on that snack, wouldn't you? Well, such a snack actually exists, but it's not something you eat...it's something you do. It's a quick, easy, short burst of exercise right before meals, dubbed an "exercise snack."
If you're shaking your head, thinking, what kind of gimmick is this, clearly, it's a gimmick to get you to exercise. And it works! Although exercise and diet are proven to prevent type 2 diabetes and related heart disease, less than 10% of Americans get the exercise they need, often saying they do not have the time. How to get folks to make the time-and figuring out exactly how much time they need and whether shortcuts can do the trick-have been areas of study for researchers.
So a team from the School of Physical Education, Sport and Exercise Sciences at the University of Otago in New Zealand co-opted the catchy phrase "exercise snack" to refer to a much less catchy but more technically descriptive term... high-intensity interval training. That's a few brief minutes of intensive exercise, such as fitness walking, running or resistance training. "Exercise snack" was coined by Harvard cardiologist L. Howard Hartley, MD, in 2007 in a column he wrote for Newsweek to define quick bursts of calorie-burning ordinary activity, such as pacing while talking on the phone or taking the stairs instead of the elevator. Studies have shown that exercise snacking in the form of high-intensity interval training is as effective as longer workouts for keeping fit and that it improves glucose control.
The researchers set off to see whether their idea of an exercise snack could help keep blood sugar from "spiking"-a problem among folks with diabetes and prediabetes whereby blood sugar goes way up after meals. Spiking is directly related to diabetes-associated cardiovascular disease, so prevention is a high priority.
The New Zealand study was small, including seven men and two women who had either prediabetes or newly diagnosed diabetes. The participants all practiced three different exercise regimens, each for five days with a break in between, to examine the impact of each regimen on blood sugar after meals.
One regimen, regarded as a traditional workout regimen, had participants do 30 minutes of moderate-intensity treadmill walking before their evening meals. Another regimen-referred to as an exercise snack-had participants do only six minutes of treadmill walking, alternating one minute at an intensive pace followed by one minute at a slow pace, a half hour before breakfast, lunch and dinner. The third exercise regimen, also a six-minute exercise snack done half an hour before each meal, involved alternating intensive one-minute walks with one-minute resistance exercises that worked the arms, back and core.
A Quickie is Better!
The researchers found that a person doesn't have to huff and puff for 30 minutes a day to keep blood sugar in check-a few minutes of intensive exercise before meals was better in preventing blood sugar from spiking. Exercise snacking (either kind described above) before breakfast reduced postmeal blood sugar by an average 17%. Although exercise snacking before lunch didn't have much of an effect on blood sugar levels, exercise snacking before dinner reduced it by an average 13%. In comparison, the 30-minute daily workout had no effect on postmeal blood sugar.
"First and most important, exercise snacks are more time-efficient," said lead researcher and doctoral candidate Monique Francois. "Running an hour or two every day can help reduce blood sugar spikes after meals, but doing this is not feasible for most people. Short, intense exercise done right before a meal gives the same benefit."
How to "Exercise Snack"
You don't have to invest in a treadmill or buy any exercise gear to exercise snack, said Francois. If you want to do it as part of a regimen for blood sugar control, simply take a quick, brisk walk before mealtime. For blood sugar control or simply overall fitness, Francois echoed the advice that Dr. Hartley gave in his Newsweek article back in 2007: Rather than driving all the way to a destination, bike, jog or walk at a moderate to fast pace either part or all the way-and take the stairs instead of an elevator or escalator when you can. Francois cautioned, though, that people with health conditions such as diabetes should discuss exercise routines with their doctors before they start them to get guidance about doing them safely and effectively. This is one case in which, instead of doing strenuous, time-consuming exercise-which many people are likely to skip precisely because it seems so onerous-giving it all you've got for a few quick minutes brings better health results. So snack away!