Building strength and muscle mass: optimize training & nutrition for longevity (AMA #71 rebroadcast)

Muscle strength typically peaks in the 30s or early 40s and declines at about 1-2% per year. After age 70, this decline significantly accelerates. Power (incorporating velocity) peaks even earlier than strength. Understanding this baseline helps in setting training goals to mitigate age-related muscle loss.

Progressive overload is the principle of continuously challenging muscles with increasing demands to force adaptation and growth. You can implement it by increasing the weight, increasing repetitions, adding more sets, decreasing rest time between sets (e.g., supersetting), or increasing time under tension during movements.

Concentric movement is when a muscle shortens while producing force (e.g., lifting a weight). Eccentric movement is when a muscle lengthens under tension (e.g., lowering a weight slowly). Concentric training builds power, while eccentric training places mechanical stress for hypertrophy. Controlling the eccentric phase is crucial for injury prevention and muscle growth.

Training intensity is a crucial variable. While muscular failure (inability to perform another rep) has benefits, training to technical failure (inability to perform another rep with good form) or in the 1-2 Reps in Reserve (RIR) range is safer and provides almost the same benefits. Beginners should aim for a higher RIR and gradually work down.

Compound exercises (squats, deadlifts, presses, rows) engage multiple muscle groups and joints simultaneously, providing the foundation for overall strength and muscle mass. Isolation exercises are also valuable but generally follow compound movements, especially if time is limited. Compound movements also build coordination and control, reducing injury risk.

Beyond one-rep max, useful metrics include standing broad jump (testing power and eccentric strength), pull-ups (with controlled eccentric), dead hang duration, wall sits, farmer's carries, and box step-ups with weight. For body composition, appendicular lean mass index (ALMI) and fat-free mass index (FFMI) from DEXA scans can track muscle mass.

The recommended protein intake for building and preserving muscle is between 1.6 to 2.4 grams per kilogram of body weight per day, roughly 0.8 to 1 gram per pound of body weight. Older individuals or those who are less active may need slightly more due to anabolic resistance.

Any significant caloric deficit, including through fasting or intermittent fasting, puts muscle mass at risk, especially if weight loss is rapid. To minimize muscle loss, it's crucial to meet your protein needs (approx. 1g/lb body weight) and maintain high levels of resistance training throughout the period of caloric restriction.

Hormones (like testosterone and cortisol), sleep, stress, and consistency are critical. Higher testosterone levels facilitate muscle gain, while chronically elevated cortisol can be catabolic. Adequate sleep is vital for recovery and muscle rebuilding. Consistent training, even a modest amount, is more effective than inconsistent, high-intensity efforts.

For younger beginners, a 3-day full-body program (e.g., Monday, Wednesday, Friday) with each workout lasting about an hour is effective. Focus on 10-20 sets per body part per week, 3-4 sets per exercise, 6-15 reps, and 90-120 seconds rest. Supersets can improve time efficiency. Start with lower intensity (3-4 RIR) and gradually move to 1-2 RIR.

Experienced lifters should focus on adapting their training to support long-term health and prevent injury, aligning with the 'Centenarian Decathlon' mental model. This might involve 'de-risking' movements (e.g., replacing heavy deadlifts with belt squats to reduce axial load), focusing on unilateral movements, and addressing deficits like connective tissue strength (e.g., calf raises for Achilles tendon health).