What would you say if I said that you could run less miles and get faster just by adding a couple of short high intensity interval workouts into your running program?
If you have ever trained for an endurance event, then you know that part of the training involves long, slow runs in order to build up your mileage. These types of runs are essential for physiological and psychological reasons. However, in order to become a faster, more efficient runner, you need to do more than just long runs. Three main factors determine endurance performance:
- Maximal oxygen uptake (VO2max): the maximum amount of oxygen that an individual can use during exercise. Elite endurance athletes have a higher VO2max and the body is better able to utilize and supply oxygen to muscles;
- Anaerobic threshold: the level of exercise intensity at which lactic acid accumulates faster that the body can get rid of it;
- Running economy: basically how efficient of a runner you are.
In order to become a faster/better runner you need to improve one or all of the above factors. The million-dollar question is how? Although most runners think running longer is better, research has shown that this is not the case.
A recent systematic review examined the short- and long-term effects of interval training on performance in recreational distance runners, compared to traditional long continuous running. All of the intervention studies used interval training for a minimum of 4 weeks and maximum of 10 weeks. Interval training consisted of repeated short to long bouts of running at close to 100% VO2max, interspersed with recovery periods. They all included 2-4 interval sessions per week, combined with traditional long, slow runs.
Overall, they discovered that interval training had beneficial effects on endurance performance, despite reductions in overall training mileage. Specific benefits of interval training versus a training program, which focused solely on long runs at low-moderate intensity included:
- Improved VO2max;
- Improved anaerobic threshold;
- Improved running economy;
- Delayed muscle fatigue;
- Ability to sustain muscular performance at faster speeds
- Activated a greater number of muscle fibers
- Runners were less likely to get injured, which could be related to increased strength, as well as decreased training volume and time.
So where do you start?
Adding at least two days of short interval runs into your running plan will improve your performance. The above authors found that the most beneficial results were with intervals of less than a minute, with a work:rest ratio of 1:1 or 1:2, performed at close to maximum intensity.
Sample Interval program:
10-minute warm-up of jogging at an easy pace, followed by 4 x 30 sec. repetitions (covering 90-200 m), with a one min. rest, repeating 4 sets. Follow this with a 10 min. cool down jog.
Interval training must be integrated into a running program with long, continuous runs. Both training regimes are needed to improve endurance performance. Workload and intensity of the interval program should change throughout the training program, according to training goals and periodization.
Garcia-Pinillosa et al. (2016). How does high-intensity intermittent training affect running performance in recreational endurance runners? Acute and chronic adaptations. A systematic review. Journal of Sport and Health Science. In press