Cardio is sold as the fat-loss tool of choice. The actual evidence shows it's a useful but secondary intervention: the calorie burn during cardio is modest, and the body compensates by reducing activity in other parts of the day. Diet plus strength training drives more sustainable fat loss.
The calorie-burn reality
45 minutes of moderate jogging burns around 350-400 calories for a 70kg woman. A medium latte and almond croissant after the run is 600 calories. The most common pattern: people exercise, get hungrier, eat more, and don't see fat loss despite the work.
NEAT (non-exercise activity thermogenesis) drops too. After hard cardio sessions, daily fidgeting, standing, and small movements decrease — the body unconsciously conserves energy. Total daily expenditure often only goes up by 100-200 calories despite the visible workout burn.
What works better for fat loss
Calorie deficit through diet (the 80% rule). Strength training to preserve muscle during deficit (otherwise muscle is lost alongside fat). Walking 8-10k steps daily (less metabolic compensation than hard cardio). Cardio 1-2x weekly for cardiovascular health, not as the primary fat-loss tool.
When cardio earns more time
You enjoy it (adherence trumps optimisation). Cardiovascular health (running, cycling improve aerobic fitness measurably). Training for an event (5K, marathon). Mental health (running has antidepressant effects independent of fat loss).
Cardio is good for you. It's just not the lever for fat loss most marketing implies. Diet + strength + steps + sleep does more — cardio is the supporting role.