It's no secret that physical inactivity is bad for health. Research shows that physical inactivity and sedentary behavior are major risk factors for obesity, insulin resistance and Type 2 diabetes. But little is known about the consequences of short-term physical inactivity.
For their study, the researchers examined the metabolic consequences of short-term increased sedentary behavior in 45 healthy adults with a mean age of 36 years. All of the participants have a mean daily step count of more than 10,000 steps and were asked to reduce their daily step count to around 1,500 steps for two weeks.
The researchers measured the participants' cardiorespiratory fitness, body composition and multi-organ insulin sensitivity at baseline, after the two-week step reduction and two weeks after the participants resumed their normal physical activity.
The team found that the participants developed "metabolic derangements" after two weeks of increased sedentary behavior. Their blood sugar and bad cholesterol levels rose, and their insulin sensitivity declined. In addition, the participants lost a little muscle mass in their legs and gained fat around their liver and abdomen. (Related: Twice as many deaths are caused by physical inactivity compared to obesity, stunning study finds.)
Fortunately, these changes were reversed after the participants resumed their normal routine. For some reason, however, some participants failed to return to quite the same level of exercise they had engaged in prior to the study. These participants now completed fewer minutes of vigorous activity each week and exhibited slight but lasting symptoms of insulin resistance.
While this lasting effect might be due to the participants' lower levels of vigorous activity, the researchers are also open to the possibility that this stemmed from genetic factors.
In another study, published in the Journals of Gerontology, researchers from McMaster University in Canada found that the consequences of increased sedentary behavior were more severe and long-lasting in overweight, prediabetic older adults.
The researchers enlisted 22 older adults who had those conditions and had a daily step count of more than 4,000 steps. The participants were asked to reduce their daily step count to less than 1,000 for two weeks and then return to their normal levels of physical activity.
The participants' blood sugar control quickly worsened during the period of increased sedentary behavior. Their insulin resistance climbed, and some of them displayed changes in their muscle tissues, indicating that they might soon lose muscle mass. A few of the participants had to be removed from the study because they were close to developing Type 2 diabetes. Meanwhile, the remaining participants' blood sugar control was not restored to pre-intervention levels.
These findings, according to lead author Chris McGlory of the Department of Kinesiology at McMaster, demonstrate that the consequences of short-term physical inactivity get amplified by increasing age and risk factors like being overweight.
"[If] it’s at all possible, don’t stop moving,” said McGlory.
While taking a vacation from exercise can be tempting, you can still incorporate simple physical activities, such as taking a walk after lunch, even during your rest period. Be creative and keep moving to stay healthy.
Read tips for maintaining a successful exercise routine at Slender.news.