It’s a common misconception that physical activity alone can counterbalance poor eating habits. Many people mistakenly believe they can simply out-exercise a bad diet. However, lasting weight loss requires much more than exercise, especially if you are using weight loss medications or have undergone weight loss surgery in the UK, such as a gastric sleeve, gastric bypass, or gastric band.
Whether your goal is to slim down or improve your overall health, understanding the balance between diet and exercise is essential for success.
Calories In vs Calories Out: Why Diet Matters More
At the core of weight management lies a simple principle: calories in versus calories out. This refers to the balance between the calories you consume through food and drink, and those your body burns through everyday activities and exercise.
Everyone has a Basal Metabolic Rate (BMR), the number of calories your body needs at rest for essential functions like breathing and digestion. Your BMR depends on factors such as age, weight, height, and physical activity level. While exercise does increase calorie expenditure, it’s very easy to overestimate the calories burned during workouts. In contrast, it’s alarmingly easy to underestimate the number of calories consumed through meals, snacks, and drinks.
For instance, a 45-minute workout may burn around 300 to 400 calories, depending on your body and intensity level. However, just one high-calorie meal or sugary drink can easily exceed this amount, potentially undoing your hard work in a matter of minutes.
Why Exercise Alone Isn’t Enough for Weight Loss
Exercise is highly beneficial for your body, but it’s not a license to eat whatever you want. Many processed foods contain hidden sugars, fats, and salts, making it effortless to consume more calories than intended. This is why weight loss after bariatric surgery or while taking weight loss medications requires careful attention to eating habits. Simply exercising more isn’t enough to achieve meaningful fat loss if high-calorie foods remain part of your daily routine.
Relying on exercise alone can also lead to an unhealthy relationship with food, where meals are only seen in terms of how much activity is needed to “burn them off.”
Registered dietitians and bariatric clinics in the UK recommend focusing on portion control, reading nutrition labels, and making mindful food choices to support weight loss goals.
The Real Benefits of Exercise
While exercise may not be the most effective method for fat loss on its own, it remains a vital component of a healthy lifestyle. The benefits of regular physical activity extend far beyond the number on the scale.
- Regular exercise can:
- Improve heart health
- Lower blood pressure
- Strengthen muscles and bones
- Support mental health by reducing stress, anxiety, and depression
- Improve sleep quality
Aim for at least 150 minutes of moderate exercise per week. This can include walking, swimming, cycling, yoga, pilates or weight training. If you’ve had a weight loss surgery or are taking weight loss medications, it’s always advisable to consult your healthcare provider before starting or adjusting your workout routine.
Finding the Right Balance for Sustainable Weight Loss
The truth is simple you can’t out-exercise a bad diet. While physical activity is important for overall wellbeing, weight loss depends far more on healthy, consistent, and balanced eating habits.
A sustainable approach combines nutritious food choices, portion control, and regular physical activity. Together, these habits can lead to long-term weight loss success and improved health whether you’ve had bariatric surgery or are using weight loss medications .
Medically Reviewed by Mr. Qutayba Almerie, MD, MSc, FRCS
Consultant Upper GI & Bariatric Surgeon, Medical Director at Phoenix Health.
