While most health and fitness enthusiasts are quite familiar with the most recent Physical Activity Guidelines for Americans, it’s not clear whether physical activity is as beneficial when concentrated in just a couple of days per week versus spread throughout the week. This is an important question because some individuals find it more convenient to be physically active during the weekend, aka “Weekend Warrior”, than during the traditional Monday through Friday workweek. A recent paper published in JAMA Internal Medicine shed light on this important issue.
The study included 350,978 apparently healthy American adults who participated in the US National Health Interview Survey. Men and women were equally represented; the sample had an average age of 41 years. About 68% of the sample was White, while 15% and 12% were Hispanic and Black, respectively. At baseline, physical activity was assessed via questionnaire. The questions focused on frequency (how often), duration (how long), and intensity (level of effort). Participants were then categorized based on their physical activity level and pattern as follows:
Physically Inactive: Less than 150 minutes per week of moderate to vigorous physical activity.
Physically Active: 150 minutes or more per week of moderate to vigorous physical activity.
The Physically Active group was further classified as follows:
- Weekend Warrior: 2 or fewer physical activity sessions per week.
- Regularly Active: 3 or more physical activity sessions per week.
Next, both the Weekend Warrior and Regularly Active groups were placed into subgroups according to the duration and intensity level of each physical activity session. For duration, the subgroups were less than 20 minutes, 20-30 minutes, 30-60 minutes, or greater than 60 minutes per session. For intensity level, the subgroups were based on the percentage of physical activity that was vigorous as opposed to moderate.Vigorous intensity was defined as activities that produce heavy sweating and large increases in breathing and heart rate.
Participants were followed for an average of 10.4 years, during which time there were 21,898 deaths. About half of all deaths were from cardiovascular disease or cancer, which was expected.
What Were the Results?
In Figure 1 below, all-cause, cardiovascular disease and cancer mortality risk among Inactive, Weekend Warrior, and Regularly Active groups are shown. In each case, while the Weekend Warrior group had lower mortality risk than the Inactive group, the risk was further reduced among the Regularly Active group.
Next, among those who were Regularly Active, the relationship between duration of each physical activity session and mortality risk was examined. When compared to the Inactive group, all-cause, cardiovascular disease, and cancer mortality was lower with longer duration of each session. For example, among those participants who were active for 30 minutes or more per session, the risk of CVD mortality was reduced by 23% when compared to those who were Inactive. Finally, among those who were either Regularly Active or Weekend Warriors, the relationship between intensity of exercise and mortality risk was examined. When compared to the Inactive group, all-cause, cardiovascular disease, and cancer mortality was lower with a greater proportion of weekly physical activity spent at vigorous as opposed to moderate intensity in both the Regularly Active and Weekend Warrior groups. Generally speaking, there was more of a benefit to performing some vigorous activity as opposed to performing all moderate intensity activity. Similar results were observed for cardiovascular disease and cancer mortality.