Health: Zone 2 cardio gains traction as sustainable workout approach

Health experts are turning to Zone 2 cardio as the foundation of sustainable training, arguing that most workouts should be performed at a lower intensity to improve endurance and fat burning. Dr. Morgan Busko, a sports medicine physician at NewYork-Presbyterian, recommends that runners spend 70 to 80 percent of their total run time in heart rate Zone 2, roughly 60 to 70 percent of a person’s maximum heart rate. At this pace, exercisers should be able to hold a conversation while running.

A New York fitness professional described Zone 2 as the “elephant” pace—steady, reliable and capable of delivering results. Jesse Ramos Junior, a trainer at BBT Fitness, told Daily Mail that Zone 2 helps the body burn fat for fuel and build endurance without burnout. He noted that many people trying to lose weight push too hard and quit; Zone 2 offers a sustainable foundation. Experts say high-intensity work remains important, with about 20 to 30 percent of sessions spent at a pace where conversation is difficult.

Dr. Busko told Business Insider that, for everyone, longer runs at a low heart rate are beneficial for building aerobic endurance, and that running slower for longer periods sets runners up to improve speed over time. The same principle applies to other aerobic activities such as cycling, swimming or elliptical training, and it aligns with a broad set of health goals beyond performance alone. Exercise at Zone 2 is associated with reduced risk factors for several conditions, including type 2 diabetes, heart disease and Alzheimer’s disease. The World Health Organization recommends everyone complete 150 to 300 minutes of moderate-intensity exercise, such as brisk walking, jogging or cycling, each week, or 75 to 150 minutes of vigorous activity as an alternative. Yet estimates suggest only about half of US adults meet these guidelines weekly.

Several experts emphasize Zone 2 for its potential to promote adherence. Because the pace is sustainable, exercisers may return to workouts more consistently and accumulate longer total exercise time without as much fatigue. High-intensity intervals still have a role, but the balance—often with the majority of training in Zone 2—appeals to people seeking steady gains and long-term consistency. While Zone 2 training is widely promoted, researchers note that the most effective mix of intensities may vary by individual and sport, and that heart-rate zones remain estimates rather than precise thresholds for everyone. Maximum heart rate is commonly estimated with the simple formula of 220 minus age, which means a 30-year-old would have an estimated max around 190 bpm and a Zone 2 target roughly 114 to 133 bpm. Wearable monitors can help people tailor workouts to their own physiology and daily condition.

Overall, health professionals say Zone 2 training offers a practical path for people seeking long-term adherence and health benefits across aerobic fitness. The approach supports consistent workouts and may help people exercise longer without excessive fatigue, potentially enabling more frequent workouts and steady improvements in health.