It is excellent that you are staying active! For optimal bone health, especially with regular gym workouts, I recommend focusing on Calcium (about 1,000 mg daily) and Vitamin D3 (600?800 IU daily) to assist with calcium absorption. Magnesium and Vitamin K2 are also highly beneficial for bone mineralization. Since you already do weight-bearing exercises, your workouts are already helping strengthen your bones. While these nutrients are best sourced from a balanced diet of dairy, leafy greens, and fish, supplements can safely bridge any gaps. I suggest a simple blood test to check your baseline levels before starting supplements, so your doctor can tailor the exact dosages for you.