I was reading an old Triathlete (June 2008 – the swimsuit issue) and I came across an article called “Crank it Up – Inject some intensity to avoid the one-speed blues” by Matt Fitzgerald. To sum it up I have felt that while my endurance is definitely building my absolute top speed is not present. The article states –
There’s a funny phenomenon in endurance sports that I like to call “becoming a one-speed athlete.” It happens to long-distance runners, cyclists and triathletes whose training becomes so focused on sustained efforts at race intensity and below that their ability to work at higher intensity levels atrophies.
The article states that this phenomenon is due to your body getting used to a set rating of perceived exertion (RPE). That limiting training to the longer endurance makes it more difficult for you to reach a higher RPE in shorter distances. I experienced this last weekend at the Heat Wave. I had plenty of cardiovascular overhead during my run but the effort seemed too hard - I wanted to run faster but I just could not pick up the pace to where I wanted it to be. Sure I ran faster than last year but my heart rate average for last year was much higher – like 10 beats per minute higher. This my fitness is improving (a good thing) but I would also like to be able to find the top gear on these shorter races. The article continues with technics to help limit this ‘one speed’ pony. One such workout is a moderate 50 – 60 mile bike followed by a maximal-effort 10 - 15 mile Time Trial (ouch) or a sustained bike workout at a set wattage about 10 – 15 % higher than your race wattage until exhaustion (45 - 60 minutes for ironman).
I’m thinking that for me I will incorporate some hard tempo runs (5k - 10k pace) and rides at higher than normal pace – more of those TT's.