Studies on high-altitude mountaineers show significant loss of strength over time, but most athletes train at much lower levels, where the impact of altitude on strength is much less. Strength training is now recognized as a vital component for endurance athletes, enhancing performance, improving running economy, and aiding injury prevention. This can be achieved through sport-specific resistance (e.g., paddles for swimming, big gears for cycling), bodyweight circuit training (including plyometrics), or gym-based weightlifting while at altitude. A relatively new and highly effective technique is Resistance Training in Hypoxia (RTH), where athletes lift weights while breathing low-oxygen air. RTH induces a high level of metabolic stress within the muscle, forcing early recruitment of high-threshold muscle fibers. This “live low-train high” RTH paradigm offers a potent way for sea-level athletes to maximize physiological adaptations beyond aerobic changes.