I have seen and been asked many questions from athletes in recent weeks regarding intervals workouts. When should they be incorporated into your training program, how long should the work efforts be, and similarly how long should the recovery last in between each effort and do I even need to do them?
Why Should I Do Interval Training?
Why should I even bother with intervals, you may ask. How does a 3-6% boost in performance sound, I reply. Studies have shown that by performing intervals (correctly) once per week, such gains in performance can be achieved. Surprisingly it is not only the novice athlete that tends to neglect speed (interval) training, even advanced athletes often overlook the need for speed despite the proven advantages of them, both psychological and physiological. Merely performing intervals of increased effort is not enough however; the key is to target a specific intensity to reap the rewards. If done correctly, both your intermediate and slow-twitch muscles will become activated to their potential during these efforts and as a result you will begin to see better muscle coordination and improved economy. In addition, they will teach your mind how to handle harder work and will spur on positive physiological adaptations. Every speed workout is like money in the bank, in that for each one you execute correctly, the payout will be tenfold when you need it on race day during the most difficult of times. Sounds pretty attractive, huh?
So What is the Correct Way to Do Interval Training?
I’m glad you asked. First, interval workouts require fresh legs and focus as you will need to have your game face on to hit the desired target intensities and reap all the benefits. The most important components of the interval workouts are: the intensities of the work and recovery intervals, the durations of those intervals, and the total time accumulated at this desired intensity within the workout. By manipulating any of these variables the effects of the workouts are changed. How they should be manipulated depends upon the distance of the events you are training for.
Optimal durations of the work bouts should be 2-to-8 minutes in length. They should be progressive and become increasingly race-specific.
The timing of your efforts is very important. If the efforts are too long, lactic acid will accumulate, VO2 max is stressed too much and you will be forced to slow down or not be able to complete the workout as planned due to undue fatigue. If they are too short, the total time at the optimal intensity is condensed and gains are reduced. Keep in mind that the goal is not to go as fast as possible for the work portion but rather to accumulate time at the desired pace. By completing these efforts at the correct intensity, namely 80-95% of VO2max, you will begin to notice significant performance improvement. Any faster and gains are nullified and injuries become more probable. This is where discipline comes into play and why I suggest that the athletes I work with add Sportiiii’s to the equipment list. This useful tool provides performance feedback without distracting an athlete from their workout. It allows runners to maintain form without looking down at their watch for split times, and for cyclist to keep their eyes on the road while remaining in an aerodynamic position - allowing both to further emphasize form and economy.
As the workouts progress, the accumulated workload increases. Recovery durations generally should be 50% to 100% of the interval time and as you become more fit the paces may feel easier. This could be a signal to shorten the recovery interval or increase the work interval.
Regardless of whether you are a short-course athlete or prefer the longer distances, there is a time and place for speed work in your repertoire. Speed training should be more heavily emphasized during the early part of the season so as to follow the principle of specificity which when applied to periodization ensures that key workouts become increasingly like your next A race.
Remember to start modest and progress slowly if you are just beginning as the body adapts best to small, consistent changes.
Jeff Vicario is an Elite TrainingBible and USA Triathlon Youth and Junior Certified Coach. He coaches athletes of all levels to extraordinary results ranging from first time racers to Ironman personal bests. For more information about Jeff’s coaching, to ask a question you’d like to see here on the TrainingPeaks blog, or to simply contact him for further information, you can email him at jvicario(at-sign)trainingbible(dot)com.