Physical Activity, Strength and Keeping Muscle

Overview

Movement affects health in many ways beyond the scale. NIDDK says physical activity may not have a big impact on weight loss, but it has important health benefits independent of weight loss itself. [1] This page covers guideline amounts, what trials show about weight, waist and muscle, and a gentle way to begin. It is educational and does not prescribe a program.

Guideline amounts for adults

NHS recommends that adults aged 19 to 64 do strengthening activities that work all major muscle groups on at least 2 days a week, plus at least 150 minutes of moderate-intensity activity or 75 minutes of vigorous-intensity activity a week, and reduce time spent sitting or lying down. [2] NHS says that if you have not exercised for some time or have medical conditions, speak to your GP first. [2] NIDDK notes federal guidelines recommend at least 150 minutes a week of moderate aerobic activity and 2 days of muscle-strengthening, and that you may need more than 300 minutes a week to reach or maintain a weight-loss goal. [3]

What the research shows

Protein and muscle

A review notes that higher-protein, energy-restricted diets preserved lean mass in several short, tightly controlled studies, while longer-term results were mixed and depended on whether people followed the plan. [8] The 2026 meta-analysis comparing medicines with lifestyle programs concludes that muscle mass can be significantly preserved by integrating resistance training, adequate protein intake and body composition monitoring into weight-loss programs. [6] This page does not give personalized protein amounts; a dietitian can do that. For older adults, see Strength training and protein for older adults and Sarcopenia and muscle loss with age.

Walking and everyday movement

Walking counts as aerobic activity. NHS says moderate activity raises your heart rate and makes you breathe faster, and one way to tell the level is whether you can still talk but not sing. [2] NHS Better Health says getting more active has benefits even if you start with 10 minutes at a time. [7]

A gentle way to start

1. Check in first if you have not been active for a while or have health conditions. [2]
2. Start small with short walks or the chair-based strength exercises NHS describes, doing them gradually more often. [9]
3. Add strength work twice a week over time and combine with your preferred cardio. [2]

Safety and when to get help

Follow your clinician's advice if you have a heart, joint or other health condition, and speak to a GP before starting if you have not exercised for some time. [2] NHS describes anorexia as trying to control weight by not eating enough food, exercising too much, or both, so if exercise feels compulsive, see Eating disorders and disordered eating. [10] Related: Healthy weight basics, Metabolism myths and Recovery after exercise.