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When it comes to improving running fitness, every workout has its place in a training plan. Three miles of easy running does not elicit the same fitness gains as three miles of tempo or interval-paced running. One is not more important than the other, and all are necessary to elicit fitness gains. Even so, many triathletes still find themselves getting stuck in a rut of logging too much easy mileage, neglecting the more high–intensity efforts. If this sounds familiar, consider the results of a study published in the Journal of Applied Physiology that demonstrate the advantages of including harder workouts in your training regimen.
Researchers at the University of Copenhagen in Denmark monitored two groups of runners over a seven-week period. One group continued their normal running and the other subscribed to a regular fartlek-style workout. After a short warm-up, this workout involved 30 seconds of jogging, 20 seconds of running at a regular training pace, and 10 seconds at an all-out sprint, four times in a row continuously. They followed that routine with a two-minute jog and then repeated the cycle two more times. After doing this three times a week for four weeks, they bumped up to completing the cycle four times for each of the remaining three weeks. While this group was doing more high-intensity running than they had done prior, they actually reduced their total weekly mileage by 50 percent. At the end of the seven-week training program they found that the group who was assigned the 30-20-10 workout improved VO2max, 1,500-meter and 5K times, and their blood pressure and cholesterol numbers, while the control group did not.
“There are numerous reasons you should consider adding fartlek workouts into your running program,” says Anthony Bagnetto, a USA Triathlon-certified coach based in New York City. “The obvious benefits include increased anaerobic capacity, greater muscular force and endurance, and an elevated neuromuscular response that comes with the higher leg turnover and quicker cadence.”
While the Danish researchers used a 30-20-10 approach, there are plenty of other ways to structure fartlek training. The word “fartlek” simply means “speed play” in Swedish, allowing you to literally play around with combining harder and faster running in one uninterrupted workout. The main thing that sets this type of training apart from interval training, for instance running 400s on a track, is the fact that the workout is continuous. Instead of stopping and starting, you’re constantly charged with changing gears.
Bagnetto says that in learning to switch between jogging, steady-paced running, and all-out efforts on the fly, you’re better equipped to respond to a competitor during a race as well. “For competitive athletes, there is nothing more sobering than seeing someone in your age group coming up behind you in the latter stages of a race,” he says. “Being able to kick into a faster pace immediately and comfortably can mean holding off a charging competitor, and fartlek runs are perfect for this kind of prep.”
The 30-20-10 Run Workout
Do a short warm-up then 30 seconds of jogging, 20 seconds of running at a regular training pace, and 10 seconds at an all-out sprint, four times in a row continuously. Follow that 5:00-minute routine with a 2:00-minute jog and then repeat the cycle two more times.