Dr. Steven Gundry and Mark Sisson have sparked a fresh conversation about exercise, longevity and the role of running, arguing that a fitness routine built around walking, strength training and occasional high-intensity work may be more sustainable for many people.
In a recent conversation, Dr. Gundry sat down with Mark Sisson, founder of Mark’s Daily Apple and author of Born to Walk, to discuss how conventional ideas about exercise have evolved and why Sisson believes walking deserves a much more prominent place in modern fitness.
Sisson, a former elite-level runner, reflected on his own experience with high-volume running. He said years of intensive training were accompanied by injuries and other health problems, prompting him to reconsider the relationship between endurance exercise, performance and long-term health.
Walking Takes Center Stage
A central theme of the discussion was the importance of regular, low-intensity movement. Sisson described walking as a fundamental human movement and argued that people can benefit from moving frequently throughout the day rather than relying exclusively on a single intense workout.
Gundry highlighted a similar idea, pointing to walking as a practical way to incorporate movement into everyday life. The conversation emphasized shorter bouts of activity, such as taking walking breaks during a workday, rather than remaining sedentary for long periods and attempting to compensate with one workout.
Sisson also discussed what he called “exercise snacking” brief periods of movement spread throughout the day. Walking, climbing stairs and other forms of everyday activity can provide opportunities to move without requiring a lengthy training session.
A Different View of Running
Sisson did not argue that running is inherently bad. Instead, he questioned whether high-volume, repetitive running should be the default exercise strategy for everyone.
He suggested that people who enjoy running or are well suited to it can continue to run, while others may benefit from emphasizing walking, resistance training and occasional sprinting.
The discussion also touched on the potential trade-offs of endurance training. Sisson pointed to injuries among recreational runners and questioned whether running alone is an effective long-term strategy for weight management and overall health.
Strength Training and Metabolic Health
The proposed approach extends beyond walking. Sisson recommended combining regular low-intensity movement with strength training to help maintain muscle and physical function as people age.
The conversation also explored “metabolic flexibility” the body’s ability to use different fuel sources depending on circumstances. Sisson connected this concept with dietary choices, exercise intensity and overall metabolic health.
However, many of the health and metabolic claims discussed in the interview represent Sisson’s interpretation of the research and should not be treated as established medical consensus without examining the underlying evidence.
Rethinking Footwear
Another major topic was footwear. Sisson argued that modern shoes can restrict natural foot movement and advocated footwear designed to provide a wider toe area, a flat sole and greater flexibility.
He also discussed his own involvement in developing minimalist footwear and said people should transition carefully rather than immediately attempting to run in minimalist shoes.
The broader message was that walking provides an opportunity to strengthen and reconnect with the feet while exposing them to different surfaces and movements.
A Simpler Fitness Message
Despite the wide-ranging discussion, the central recommendation was relatively simple: move more.
Rather than making exercise exclusively about calories, distance or performance metrics, Sisson encouraged people to incorporate movement throughout the day. Walking outdoors, spending time on varied terrain and maintaining strength were presented as key components of his approach to healthy aging.
The conversation ultimately challenged the idea that harder exercise is always better. For Sisson, a sustainable fitness routine may involve frequent walking, regular strength training and occasional higher-intensity activity, rather than relying on long-distance running as the foundation.
For people considering changes to their exercise routine, individual factors including age, fitness level, injuries and medical conditions can affect what type and intensity of exercise is appropriate. A healthcare or exercise professional can help tailor a program accordingly.