People who follow a structured exercise program at their local clinic get better at using oxygen during physical activity, making them more physically fit—even if they don’t lose weight.

Overweight and obese adults who complete a 12-week supervised aerobic exercise program burning about 10.5 megajoules per week improve their cardiovascular fitness similarly, regardless of whether they are male or premenopausal female, even if men start with higher fitness levels.

People who join a group program at their clinic to exercise and eat better end up being much more active over time, while those who just get general advice don’t change much.

Eating very few carbs and more fats for 12 weeks doesn't improve the maximum oxygen your body can use during exercise in people with excess body fat when measured in absolute terms.

A 3-month program with diet changes, strength training, and intense workouts helped older adults with obesity and type 2 diabetes lose fat and keep or gain muscle — and those benefits lasted for at least 6 months after the program ended.

In adults with overweight or obesity, aerobic exercise and combined exercise programs improve cardiorespiratory fitness, measured as VO2peak, with aerobic exercise leading to the greatest gains; resistance training alone has little effect on this measure.