This type of workout is performed at an intensity that is above VT1 but below your lactate threshold, past the point where breathing is comfortable but below the point where breathing is labored. This intensity has been referred to as "the black hole" because at this intensity you will become fatigued but it won't be intense enough to promote optimal adaptations (Foster & Porcari, 399). If that's the case then why bother?
Joe Friel refers to this intensity as "the most important of all the advanced abilities for triathlons of all durations" (Friel, 24). While there aren't as many adaptations occurring as during a long slow run or short all out intervals, positive adaptations are still occurring. It is during longish steady state bouts at this intensity that cardiac efficiency is improved which in turn increases the intensity of work that can be performed at VT1. When working at this intensity your body's ability to utilize fat for fuel is improved as well (Foster & Porcari, 398). In my opinion work at this intensity also plays a role psychologically. For longer races this may very well be your race pace so it is important to spend time here. While it may be uncomfortable, you will realize that you are capable of maintaining the pace longer than you might think.
When and How to implement tempo training.
Tempo training should be done in the base period after you have built up about a month of aerobic base. For running, I like to do periods of about 5 minutes at Zone 3 intensity with about 5 minutes rest in between. To progress it I will either add more intervals, increase the duration of the interval, decrease the rest interval, or employ a mixture of the three. For riding, the intervals would be longer or, if you are up for it, a steady 30 minutes to an hour at Zone 3 depending on the length of your race.
There you have it, one more tool in your training toolbox to help you reach your true potential come race day.
- Friel, Joe. "Intensity." The Triathlete's Training Bible. Boulder, CO: VeloPress, 2009. 46. Print.
- Bryant, Cedric X., and Daniel J. Green. "Cardiorespiratory Training."ACE personal trainer manual : the ultimate resource for fitness professionals. 4th ed. San Diego, CA: American Council on Exercise, 2010. 398. Print.
- Friel, Joe, and Charlie Layton. "Your Fitness." Your Best Triathlon: Advanced Training for Serious Triathletes. Boulder, CO: Velo, 2010. 24. Print.