Obesity can significantly alter the way your body burns calories, presenting unique challenges in weight management. Despite the seemingly straightforward equation of consuming fewer calories than you burn, individuals with obesity often face complications that affect both their metabolism and overall weight loss efforts.
A recent study published in Obesity explored the physiological hurdles encountered by people with obesity, particularly focusing on energy expenditure. Researchers monitored two groups—one with obesity and another at a healthy weight—over a span of five days. Participants adhered to a structured schedule for eating, sleeping, and exercising while researchers measured their blood and energy expenditure. Results revealed that individuals with obesity burned fewer calories during waking hours and expended more energy at night compared to their healthier counterparts. Additionally, they exhibited higher daytime insulin levels, indicating greater effort required to manage glucose.
Dr. Andrew McHill, the study’s lead author and assistant professor at Oregon Health & Science University, acknowledged the uncertainty surrounding these findings. “We observed a distinct pattern in energy expenditure, but it’s unclear whether a lower daytime expenditure is a cause or consequence of obesity,” he said. The key takeaway is that individuals with obesity face a more challenging path to weight loss, requiring more effort to achieve comparable results.
Metabolism Fundamentals
Metabolism involves converting food and oxygen into energy to support bodily functions such as breathing, digestion, and physical activity. The rate at which your body expends energy depends on several factors:
Resting Metabolic Rate (RMR): This represents the calories burned at rest to maintain basic physiological functions, accounting for 60-70% of total daily energy expenditure. It is influenced by genetics, activity levels, sleep, and stress.
Diet-Induced Thermogenesis (DIT): Also known as the thermic effect of food, DIT measures the energy required to digest and metabolize food, contributing 5-15% to total energy expenditure.
Physical Activity: This includes calories burned through structured exercise (aerobic and resistance training) and non-exercise activity thermogenesis (NEAT)—the energy expended on daily movements like walking, cleaning, and other tasks.
Boosting Metabolism through Exercise
Exercise is a critical factor in increasing calorie burn and improving overall health. Both aerobic and resistance exercises play significant roles:
Aerobic Exercise: Activities like walking, biking, and swimming increase heart rate and caloric expenditure. Studies indicate that moderate to high-intensity aerobic exercise is particularly effective in reducing visceral fat, with recommendations suggesting 150 minutes of moderate or 75 minutes of vigorous aerobic exercise per week. Short bouts of activity throughout the day also offer benefits.
High-Intensity Interval Training (HIIT): HIIT involves alternating between intense exercise and recovery periods. It not only burns calories efficiently during the workout but also continues to elevate metabolism post-exercise through excess post-exercise oxygen consumption (EPOC).
Resistance Training: Building muscle through strength training can enhance resting metabolism since muscle tissue burns more calories than fat. The Physical Activity Guidelines advocate for at least two strength-training sessions per week. Resistance training also helps counteract muscle loss associated with calorie restriction during weight loss efforts.
Daily Activities and NEAT
Incorporating more movement into daily routines is crucial for boosting metabolism. Simple activities like climbing stairs, walking, or standing instead of sitting can significantly increase calorie expenditure. A study in the Journal of Exercise Nutrition & Biochemistry found that NEAT contributes substantially to daily energy expenditure in people with obesity, often surpassing the calories burned during structured exercise.
Conclusion
The most important strategy for improving metabolism and managing obesity is to focus on increasing overall physical activity rather than solely concentrating on calorie counts. “It’s not just about achieving a high heart rate,” notes Dr. Carrie Jaworski, associate director of Sports Performance at Intermountain Health. “It’s about consistent movement and engaging in a variety of activities that use different muscle groups.”
Improving metabolic health through exercise and daily activities can set the foundation for long-term success in weight management and overall well-being.
