They found that you can maintain your endurance for up to 15 weeks—nearly four months!—by doing just two-thirds of your usual volume (about five hours if you usually do eight) as long as you make those sessions count by hitting your usual target heart rate. You can maintain your VO2 max (the maximum amount of oxygen you can use during exercise; a hallmark of endurance performance) by doing half that amount, so long as you maintain the same frequency (days a week) and intensity of your usual exercise.
When it comes to keeping your muscles strong, you can squeak by with just one session of strength training per week and one set per exercise, again, as long as you’re lifting at least as much weight as you typically do, and the final rep requires close to your max effort.
The researchers based most of their endurance conclusions on a series of studies by the same team who put a group of volunteers through a rigorous routine of 40 minutes of cycling or running, including intensities that hit 90 to 100 percent of their maximum heart rate, six days a week for 10 weeks, and then spent 15 weeks testing the minimum amount of training frequency, duration, and intensity they could do to maintain their fitness gains.
When it came to endurance, the riders and runners could maintain their long-term exercise endurance (maximal exercise bouts lasting one to three hours) even if they reduced their overall volume by 33 percent—so in this case, 26 minutes a session. They could maintain their short-term endurance (maximal bouts of exercise lasting four to eight minutes) even if they reduced their volume twice as much—66 percent, or 13 minutes—as long as they maintained the same frequency and intensity of training.
The riders and runners could maintain their VO2 max with just two sessions a week (hello weekend warriors!), so long as their overall volume and intensity remained the same.
Though there wasn’t enough research on athletes specifically, the researchers drew some conclusions from tapering research that lead author Barry Spiering, Ph.D., a scientist with U.S. Army Research Institute of Environmental Medicine, told Bicycling he believes would apply to non-professional athletes like cycling and running enthusiasts.
“Several review papers from the ‘tapering’ research realm clearly indicate that athletes can maintain—or even enhance—their endurance performance for up to 4 weeks by reducing training frequency by up to [about] 20 percent, reducing training volume by 60 to 90 percent, and by maintaining—or even increasing—exercise intensity,” the authors wrote in the study.