Depending on how you want to use the phrase, here are a few ways to write "weight fitness" more naturally: For Bodyweight Training
If you are referring to fitness in relation to your size or body composition, use: Healthy weight Body composition Writing Weightlifting Notation weight fitness
If you mean exercising using only your own body as resistance, use: Bodyweight training Calisthenics For Lifting Weights Depending on how you want to use the
If you are trying to write down your workout progress (proper notation), the standard way to record it in a journal is: (e.g., "165 lbs x 5 x 3"). Which of these fits what you were trying to say? Lifting Notation: Reps are Always Second weight fitness
If you mean exercising with external weights like dumbbells or machines, use: Strength training Weightlifting Resistance training For Health Goals