The explosion of New Year’s fitness fads is nothing new. The biggest debate among endurance athletes pits the benefits of high intensity training against long duration, medium to low intensity training.

Many of the athletes I work with have emotional connections to their “go-hard” sessions. They mistakenly interpret high intensity as quality and low intensity as a waste of time.

Most people think you have to train fast in order to get faster. To be clear, training slower will make you faster.

The reasons are because of your physiology, specifically, the aerobic capacity of your slow twitch (ST) muscle fibers. ST fibers provide the pathways for removing by-products out of working muscles. ST fibers need to be programmed in an aerobic state, and the not-so-good news is that this takes time. The duration you can sustain work depends on aerobic capacity. In short, the greater your aerobic capacity, the longer you will be able to sustain work.

Almost every athlete that I test suffers to varying degrees, with compromised aerobic energy systems. This includes elites. Here is the rub: long distance aerobic training is not sexy. Building endurance takes time and patience.

Working with athletes of all stripes, I approach seasonal training programs as a system of investments and withdrawals. We purposely “train” energy systems while we “practice” sport specific skills. The goal of our training plan is to “deposit” as many investments as possible in to our fitness account.

When the time comes (race; specific VO2max training sessions) to make a withdrawal, we want to have access to well-developed energy systems. And we want the sport specific skills so as to deliver a personal best effort. I am thankful each time I am told that I race fast. Honestly, it appears fast because the majority of the field ends up walking.