Active Voice: If You Sit – Make Sure You Are Fit!
By Javaid Nauman, Ph.D. and Ulrik Wisløff, Ph.D.
Viewpoints presented in SMB commentaries reflect opinions of the authors and do not necessarily reflect positions or policies of ACSM.
Javaid Nauman, Ph.D., is a senior researcher in the K.G. Jebsen Center for Exercise in Medicine, at the Norwegian University of Science and Technology (NTNU) in Trondheim, Norway. He is an expert on epidemiological research related to physical activity and cardiovascular health.
Ulrik Wisløff, Ph.D., heads the K.G. Jebsen Center for Exercise in Medicine at NTNU. The research group at the center (www.ntnu.no/cerg) has 55 staff members (55 percent women, 30 percent international) and is truly transdisciplinary and translational. The staff includes physiologists, molecular biologists, sociologists, nurses, physiotherapists, medical doctors, bio-engineers, nutritionists, biostatisticians and epidemiologists.
This commentary presents Dr. Nauman’s and Dr. Wisløff’s views on the topic of a research article which they had published with their colleagues in the April 2016 issue of Medicine & Science in Sports & Exercise® (MSSE). This research article also was the subject of a news media story that appeared in ABC News, The Australian Broadcasting Corporation.
There is overwhelming evidence that prolonged sedentary time is associated with harmful health effects, even among people who meet the public health guidelines for physical activity. On top of this, the ubiquitous nature of sedentary behavior is likely to increase with further innovations in technologies. Cardiorespiratory fitness, on the other hand, seems to be the single best predictor of cardiovascular health and mortality. An interesting question is whether the effect of high fitness levels reduce or abolish the health risk associated with prolonged sedentary behavior.
In our study, published in the April 2016 issue of MSSE, we used data of 26,483 (14,209 women) healthy Norwegians to examine the associations between sedentary time and a cluster of cardiovascular risk factors such as a wider waist, hypertension, high triglycerides and low HDL-cholesterol. As expected, and in line with previous research, excessive sitting during the day was associated with high risk of having a clustering of cardiovascular risk factors, independent of the amount of physical activity that participants reported.
Further, we investigated whether cardiorespiratory fitness could modify the deleterious health consequences related to high sedentary time. We clearly observed that high levels of cardiorespiratory fitness compensate for the health risks associated with prolonged sedentary time. Interestingly, fit men and women were protected against health risks of excessive sitting, whether or not they met the current recommendations of physical activity.
Our findings may have huge implications for people who sit for long periods and would like to know what to do to protect their health. There are ways to reduce time spent in sedentary situations during a day: breaking up sitting time by walking around the office, or standing up instead of sitting some of the time – but, more importantly and more realistically for most people, these results strongly suggest that it can be most beneficial to indulge in physical activity that increases cardiorespiratory fitness. Our data further shows that men and women who exercise at a lower total volume (less than 75 minutes per week), but high intensity (where you puff and pant, and it’s hard to speak more than a few words) have fitness levels comparable to those who exercise at high volume (more than 150 minutes per week) and moderate intensity (where you can talk, but not sing).
Take home message: If you sit, make sure you are fit!