Both strength training and nutrition are important and play different yet interconnected roles in overall health and fitness. Their relative importance can depend on an individual's specific goals, but both are integral parts of a balanced and effective health and fitness regimen.

1. Strength Training: Strength training, which involves exercises that improve muscle strength and endurance, is essential for maintaining and improving physical fitness. It not only helps to build and tone muscles but also contributes to better bone health, better body composition, improved physical function, and a lowered risk of chronic diseases.

2. Nutrition: Proper nutrition provides the body with the fuel it needs for physical activity and daily life. It also supplies the necessary nutrients to recover and adapt from exercise, maintain and build muscle mass, and support overall health. A balanced diet can help prevent nutrient deficiencies, boost energy levels, improve recovery, and contribute to better overall health.

If your goal is muscle gain, for instance, you could lift weights all day (strength training), but if you don't consume enough protein and calories, your body won't have the resources to build new muscle tissue, and your efforts could be wasted. Conversely, you can have the perfect diet, but without strength training or some other form of exercise, your body composition and overall fitness might not improve as much as they could.

So, it's not really a question of either-or. Instead, think of strength training and nutrition as two equally vital components of your overall health and fitness plan.