A majority of my athletes sign up for coaching with a primary goal in mind: run faster.
There are many types of workouts you can include in your training to get faster: tempo runs, speed workouts, and hill repeats. Speedwork is a broad term that can encompass many different types of workouts, one of the most effective of which is VO2max intervals.
VO2max is a technical term that refers to how much oxygen you consume during a run. (This article explains more about VO2max and its relationship to running.) The higher your VO2max, the more oxygen you consume and deliver to your muscles, and the faster you run.
When most runners think of VO2max intervals, they think of workouts done the track, such as 6 x 800m (½ mile or two laps around a standard track). However, you don’t need to hit the track in order to run fast. Time-based VO2max intervals on the road will increase your speed. The road will also add variation in terrain, which decreases risk of injury (especially if you are prone to IT band syndrome or runner’s knee) and make your workouts more race specific for races on the road.
Yes, time! There’s nothing magical about 800 meters (½ mile) on the track. Your physiological systems don’t know pace and distance – they respond to time and effort.
The same workout could actually elicit different physiological responses from different levels of runners. Sub-elite athletes may complete 1K repeats at in less than 4 minutes, while back-of-the-pack runners may take over 6 minutes to run 1K. The sub-elite runner is running an appropriately hard VO2max workout, while the slower runner will be running a workout that is too physically demanding and that results in either slowing down or risking injury.
Research indicates that intervals lasting 3-5 minutes are optimal for improving your VO2max and aerobic capacity. Running at VO2max for less than 3 minutes and you may not fully reach your VO2max in the workout, while running at over 5 minutes makes it too strenuous to hold the appropriate pace. By running for time instead of distance, you keep the workout in the appropriate zone, no matter what level of runner you are.
You don’t want to skimp on the recovery intervals during VO2max interval workouts. You need to slow down during the recovery intervals and take your time to recover in order to keep running hard in the subsequent intervals.
VO2Max Interval Workouts
5 minute warm up at easy run pace
4 x 3 minutes hard, 2-3 minutes recovery jog
5 minute cool down at easy pace
15-20 minute warm-up at easy run pace
3-4 x 5 minutes at 3K-5K race effort, 3-4 minutes recovery jog in between
15-20 minute cool down at easy run pace
For the hard intervals, you want to run about a 8 on a scale of 1-10 (1 being a light jog, 10 being an all-out sprint). Jog as lightly as you need to during the recovery intervals to bring your breathing back to normal. For most runners, running at VO2max means 3K (2-mile) race effort or slightly faster than 5K race effort.
Do you prefer to run by time or distance for speedwork?