Playing with Speed Intervals
Completed within a continuous workout, such as a longer run or climb, the speed interval typically lasts for at least 45 minutes. After a good warm-up, many people begin the speed interval with a few minutes of a sustained increase in effort. This effort shouldn’t be all out, but a bump of 15 to 20 seconds per mile from your normal distance aerobic pace. This continues the warm-up process and readies your muscles and body for the gear changes that make up the speed interval workout. After this period, you are ready to play. It consists of increases in pace of varying duration and intensity, always returning to your aerobic distance pace. This could be a few quick steps thrown in every 50 meters – to simulate a bump in pace or a few difficult steps to get through an awkward section of a climb – or a sprint of 50-60 meters every few hundred meters, simulating a short stretch of steep climbing. Longer efforts of one to several minutes can be used, as well as harder efforts up hills, with recovery over the top and on the descent. One of the main points of the speed interval is that it is continuous. After your harder efforts, you should return to your aerobic distance pace. If you can’t sustain this and you find your pace slowing, back off the intensity of your harder efforts.
Speed intervals have benefits for climbers throughout the different phases of a training plan. Early on in training, the goal is base fitness and building aerobic endurance. While aerobic endurance is incredibly important to the sport of mountaineering, the long slow nature of these workouts can leave athletes feeling sluggish and with a difficult time increasing the pace. During this phase, speed intervals are a great way to maintain your ability to switch gears mid workout. As you move into your threshold building phase, speed intervals are a great mid intensity interval workout that helps train your body to recover between efforts – important in a sport where a few more difficult steps at altitude can leave you gasping for breath. Experiment with different formulas, and try throwing these workouts into your plan once or twice a week. This workout is a great way to add some creative freedom to your weekly training regimen. Lastly, don’t forget the “play” in “speed play”!
Adapted from Wikipedia