"If you haven't trained with any focus by the time you're 30, you need to be," says Lyon. Everyone's body is different, but if you can, she recommends a combination of cardiovascular activity (specifically zone 2 training) and resistance training. Zone 2 training really just refers to any cardio workout that gets your heart pumping to the point where you can still hold a conversation, but it might be difficult to do so. "That zone 2 training is critical for mitochondria," notes Lyon. "It's important for glucose utilization for the foods that you're eating, and overall it provides a base."

However, it's not enough: "In your 30s, I really believe everybody should be doing three to four days a week of hypertrophy training," she adds. Hypertrophy training is all about increasing muscle mass, namely through weight training. "As opposed to [using] much heavier weight and lower volume, the volume is important," Lyon adds. (Meaning, more sets and reps with less intensity.) "This is really about growing your muscles," she notes, and strong muscles are crucial for sustaining longevity.

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3 Research-Backed Tips To Make Your Muscles Act Younger - mindbodygreen