1. Increase calorie intake: Thin people need to consume more calories every day than people with normal weight to provide enough energy for muscle growth. This can be achieved by increasing the intake of carbohydrates and protein.

2. Strength training: Strength training is one of the most effective ways to increase muscle mass. You can choose to use free weight equipment or equipment to assist training, training 3-5 times a week, and each training time should not exceed 1 hour.

3. Ensure adequate rest: Muscle growth requires sufficient rest time, so thin people need to ensure adequate sleep time every day to avoid excessive fatigue and overtraining.

4. Supplement nutrition: Thin people can promote muscle growth by supplementing protein powder, amino acids, vitamin D and other nutrients, but you need to pay attention to choosing products that suit you and follow the correct use method.

5. Stick to a long-term plan: Muscle gain requires long-term persistence and hard work, and you can't expect to see obvious results overnight. Therefore, thin people need to make a reasonable exercise plan and stick to it.