Dr. Madhur Verma, Assistant Professor, Dept. of Community; Family Medicine, AIIMS, Bathinda, Punjab; and Dr Sanjay Kalra, DM (AIIMS), Treasurer, International Society of Endocrinology; Bharti Hospital, Karnal, Haryana
Taking frequent short breaks that involve walking or squatting can help improve blood glucose control in overweight and obese men better than just sitting continuously or a single long walking session, suggests a study published in The Scandinavian Journal of Medicine & Science in Sports.1
In this randomized four-arm crossover study, 18 overweight and obese men, with mean age 21.0 years and mean BMI of 28.8 kg/m2 were divided into four groups:
- SIT (uninterrupted sitting for 8.5 hours and interrupted sitting with matched energy expenditure and duration but different muscle activity)
- ONE (30-minute walking session at 4 km/hour)
- WALK (sitting interrupted with 3-minute walking sessions at 4 km/hour every 45 minutes) and
- SQUAT (Sitting interrupted with squatting sessions every 45 minutes, 10 times)
The net incremental area under the curve (netiAUC) for glucose was measured to compare the glucose response between different circumstances. The effects on glucose netiAUC were predicted using electromyogram (EMG) patterns for quadriceps, hamstring and gluteal muscles, including averaged muscle EMG amplitude (aEMG) and EMG activity duration.
This study aimed to explore how different physical activities, matched for energy expenditure and duration but varying in muscle activity, influence glucose regulation.
Glucose netiAUC was significantly lower when sitting was interrupted with each physical activity interruption (ONE 9.2 mmol/L/hour, WALK 7.9 mmol/L/hour and SQUAT 7.9 mmol/L/hour) than with uninterrupted sitting (SIT 10.2 mmol/L/hour) (all p < 0.05).
Additionally, compared to compared to a single walking session (ONE), both intermittent walking (WALK) and squatting (SQUAT) produced a significantly reduced glucose netiAUC, which was statistically significant (both p < 0.05).
Comparison of muscle activity and glucose response revealed that increased aEMG in quadriceps was associated with a reduction in postprandial glycemic response (-0.383 mmol/L/hour; p < 0.001). Increased aEMG in gluteal muscles was also associated with a reduction in postprandial glycemic response (-0.322 mmol/L/hour; p = 0.022).
This study illustrates that all types of physical activity to interrupt prolonged sitting reduced glucose compared to uninterrupted sitting. But short and frequent walks or squats were more effective than a single longer walking session. These superior benefits are linked to higher intensity muscle activity, particularly in the quadriceps and gluteal muscles, during transitions from sitting to physical activity.
This study therefore highlights the importance of incorporating regular, short physical activity breaks into periods of prolonged sitting to enhance metabolic health, particularly in overweight and obese individuals.
Reference
- Ying Gao, et al. Enhanced muscle activity during interrupted sitting improves glycemic control in overweight and obese men. Scand J Med Sci Sports. 2024 Apr;34(4):e14628. doi: 10.1111/sms.14628.