One of my athletes Pete McLean headed over to China for Ironman in April. Pete has been a long time friend (we are both ‘famous’ for our picture on the 05 IMWA poster side by side running ;-)). I coached Pete up to IMNZ in 09 where he narrowly missed his Kona dream by 2 minutes but did get his first sub10 time. With the start of a new job, there were to be no more shots of qualifying for a while.
What does this have to do with aerobic capacity you ask? Well Pete gave me a S.O.S call 5 weeks ago to write him a plan for IM China… he wasn’t going to race until he found out there was no refund on his travel arrangement. Now Pete had been doing some training so it wasn’t from scratch but he also just come back from holiday’s in Thailand where he got small amounts of training done, but not much.
So this finally leads me to aerobic capacity, which is the ability of the heart to pump large volumes of blood (which contains oxygen) to the working muscles with every beat. This is called ‘stroke volume’ and pretty much sums up your aerobic capacity. Thus the purpose of training is to get improvements in your stroke volume. Faster athletes have greater aerobic capacities.
There are two ways to develop aerobic capacity; through high volume or through repeated short high intensity intervals. The high intensity interval model produces greater and faster increases in stroke volume compared with high volume training and it is a big reason why I like it so much. It makes sense, especially in the development phase of training. We do less total hours, but work differing systems hard, thus we see big improvements in aerobic capacity. We also see better body compositions with this type of training but the thing I like the most is that we’re able to increase our ‘cruising’ speed and not cannibalize our bodies with high volume.
The cool thing with our increase in cruise pace/power is that when we have to do the race specific volumes in that last little phase before the race, we get that much more out of the training and can soak up the load more efficiently.
Pete got a pretty tough 5 week program which had some volume but much more short, high quality sessions purely because of the lack of time… but we were able to elicit a big enough response in stroke volume thus aerobic capacity for Pete to not only complete IM China but compete hard in his age group and secure that much wanted Kona slot and got to fulfill a dream of racing in Kona. Nothing like getting to high five Pete on his way down Alii Drive towards the finish!
So in summary we can do loads less volume for the majority of our prep and focus on the quickest way to develop stroke volume and thus cruising pace/power. While also developing skills and triathlon specific strength.