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Q: When training for a 70.3 or Ironman, should I do short intervals or just try to log as many miles as I can?
A: The reality is that any single stimulus or training approach will reach a plateau in terms of response and improvements in fitness, with results either coming in very small increments, or worse, an actual regression of fitness. This can be expected after about 16 weeks of training, maybe sooner. Be able to recognize when you are reaching this plateau, and change the type of training and stimulus you give your body in order to keep improving. If you’ve been doing a lot of miles, interval training will likely help, and vice versa.
But make sure the training approach and intensities specifically match the demands of the race. For instance, attacks and surges don’t match the steady-state activity of a long-course triathlon bike or run leg. Also, consider your goals. If you’re a new triathlete and just looking to finish an event, simply putting in miles and volume will likely be an effective strategy, as training intensity is basically the same as race-day intensity. The more competitive athlete can benefit from interval training, to better represent the higher intensities of race day.
Given the general aerobic volume of training for long-course triathletes, especially in Ironman training, an early-season approach that includes shorter, more intense interval training will likely benefit many triathletes, especially those who haven’t utilized this type of training in many seasons.
In general, your body responds well to variance, so keep this in mind when planning your training, and you’ll likely be successful using either or both strategies.
Jim Vance is an elite endurance sports coach, author, and sport technology and training consultant based in San Diego, California. He has coached Olympians, world champions, and national champions across short- and long-course disciplines, and is the expert coach behind 10 Weeks to Your Best 70.3.