All of us snack on food from time when we’re hungry and hope that it wouldn’t raise our blood sugar too much. But I wonder how many of us take "exercise snacks."
New studies on food and exercise snacks point us in different directions. Food snacking may not be what it’s cracked up to be, and I will report on that study soon. But a new concept of exercise snacking is showing that brief but intense exercise before meals can help us manage our diabetes better.
In the paragraph above I emphasized the phrase "before meals" because we already knew that when we get exercise after a big meal we can quickly bring down our blood sugar level. That’s a good strategy that I have followed myself ever since my late wife asked me after dinner one evening what she could do to reverse a high level somewhere above 200. We went out for a moderate 10 to 15 minute walk, and when we got back home and she tested again her level had dropped to little above 100.
That was much better, but prevention is always better than a cure. Exercise snacking helps prevent our levels from going too high in the first place, according to a new study by exercise scientists and medicine researchers in New Zealand, Australia, and the U.K.
The journal of the European Association for the Study of Diabetes, Diabetologia, published their research in its May 2014 issue as ""˜Exercise snacks’ before meals: a novel strategy to improve glycaemic control in individuals with insulin resistance." Only the abstract is online, and the journal asks an exorbitant $39.95 for a copy of the article, but the corresponding author, Professor James D. Cotter of the University of Otago in Dunedin, New Zealand, kindly emailed me a copy of the full-text.
The study showed that brief bursts of intense exercise before meals helps people with insulin resistance to control their blood sugar better than the standard recommendation to get one daily 30-minute bout of moderate exercise.
The authors use the term "exercise snacks" to describe these little bits of exercise, perhaps implying that they invented this term. They didn’t. L. Howard Hartley, MD, an associate professor at the Harvard Medical School, used the term earlier.
"We felt bad for not having acknowledged that he had used the term exercise snack in a Newsweek report in 2007," Dr. Cotter told me. Certainly, however, Dr. Cotter’s team is the first to study the advantages of brief bursts of exercise to help us manage our blood sugar.
They used a crossover design, which means that each of the people in the study acts as his or her own control. Consequently, the questions can be answered with a much smaller number of people. Two women and seven men got blood tests showing that they had insulin resistance and weren’t taking any heart medicine or medication for diabetes. The blood tests show that two of the people studied had type 2 diabetes that they didn’t already know they had.
The study found that exercise snacking routines of six 1-minute intense walks at 90 percent of maximal heart rate completed half an hour before break, lunch, and dinner with one minute of slow walking recovery time after each minute of intense exercise controlled blood sugar more effectively than the traditional continuous exercise. Likewise, "composite exercise snacking," which included resistance-based exercise, also worked better than traditional recommendations.
Both exercise snacking and composite exercise snacking reduced post-meal blood sugar. It was 17 percent better than no exercise at breakfast and 13 percent better traditional exercise at dinner for a daily average reduction of 12 percent. The effects on levels after lunch were not clear. The reductions in blood sugar level even continued into the second day after the exercise.
Exercise snacking is a powerful tool to keep our blood sugar levels in check before meals. The people in the study also enjoyed this way to get the exercise we all need far more than the longer traditional exercise recommendations. Have a happy and health exercise snack!