A basic knowledge of how your body works and treatment of simple injuries an go far.
Warm ups and cool downs are always the rule; and never the exception.
Should you feel chest pain (or even discomfort), shortness of breath, sudden or undue fatigue, you should stop immediately.
Many exercises involve the low back.
Make sure you know how to lift correctly.
Wear proper clothing, especially shoes.
Make sure you remain hydrated, especially in the summer months.
Prevention is the key so watch the above video to learn how to protect your body and maximize your workout!