While earlier studies found that just a few days of eating too much and exercising too little could have long-term negative impacts on the body, a new study, published in the Journal of Physiology, shows that daily exercise counters many of these effects.
As part of the study, led by researchers in the University’s Department for Health, 26 healthy young men were asked to reduce their physical activity over a period of one week. Half the group then exercised daily on a treadmill for 45 minutes, while the other half remained inactive.
Everyone who was part of the study was asked to overeat. The non-exercising group increased their kilojoule intake by 50 per cent, while the exercising group increased theirs by 75 per cent, ensuring everybody’s daily energy surplus (the extra kilojoules they received beyond what they burned) remained the same.
After just one week, both groups had blood insulin measured and biopsies of fat tissue taken, with striking results. The non-exercising group showed an unhealthy decline in their blood sugar control, whilst the exercising group had stable blood sugar levels. The activation of genes within fat cells in the non-exercising group were also found to be negatively changed to those levels needed for a well-functioning metabolism.
Senior author on the paper, Dr Dylan Thompson explains: “A critical feature of our experiment is that we matched the energy surplus between groups, so the exercising group consumed even more energy and were still better off at the end of the week.
“If you are facing a period of overconsumption and inactivity this Christmas, then our study shows that a daily bout of exercise will prevent many of the negative changes in the way in which your body handles sugar, even if you do still gain weight.”
Dr James Betts, one of the researchers also involved, said: “This new research shows that the picture is more sophisticated than ‘energy’ alone. Exercise has positive effects even when we are actively storing energy and gaining weight.”
Commenting on the findings, Dr Jean-Philippe Walhin added: “Short term overfeeding and reduced physical activity had a dramatic impact on the overall metabolic health of the participants and on various key genes within fat tissue. However, even though energy was still being stored, regular exercise prevented many of the long-term negative changes from taking place.”
