Today I started my final six week block of training before Superfrog on September 11. My swim with Mission Valley YMCA Masters was great, with a lot of threshold and suprathreshold work (300’s and 200’s). This evening I was struggling finding the motivation to get out on the bike. I was starting something new (5 minute intervals), I hadn’t selected a section of road to do them on, and it was fairly hot out. I knew I needed to be psyched, because the workout was going to be tough and require a lot of effort and focus. I really wanted to do these intervals up Torrey, a nice steady climb that would provide me a great place for a steady effort. Instead I opted for something close to home. Although it was mostly up hill, the climb is gradual, with some flat and downhill sections too. It required me to shift gears frequently to keep the power up. Overall I thought it was a lot of fun doing these intervals because it required different skills such as changing cadence and position on the bike as well as shifting frequently. Although these intervals hurt, I found I enjoyed them a lot more than the shorter intervals. Below are the results:



Max HR


























Today I set a new Personal Best for my 5 minute power. My previous best was 404 watts, done on 6/25/2011 and 9/6/2009. I am planning on doing these intervals again in four weeks, so I’ll have another opportunity to surpass the 409 watt mark.

These intervals are rather timely since Joe Friel just posted on his blog about improving endurance through High Intensity Training (HIT), which he goes on to describe as VO2 Max training. Endurance athletes are limited by their VO2 Max, or the amount of oxygen they are physiologically able to deliver from to their tissues. Age and genetics are definitely factors in how high your VO2 Max can actually be, but HIT has proven to improve you VO2 Max.

For my threshold power (337 Watts), my VO2 Max Zone (Zone 5) is 357-407, which you can see I was at the upper end of. In the wattage group there has been a lot of discussion of how long of interval is ideal for VO2 Max training, 3, 4, or 5 minutes. Longer than 5 minutes is considered too long to be able to hold the VO2 Max power. Shorter than 5 minutes isn’t considered effective either, because the beginning portion of the interval is actually bringing your heart rate up, and you are just warming up to the point of physiologically being at your VO2 Max. The argument then becomes, if it takes 2 minutes to get to your VO2 Max, with a 3 minute interval you are only getting 1 minute at VO2 Max, but with a 5 minute interval you are getting 3 minutes of benefit. It’s interesting to a point how coaches, physiologists, and athletes can argue such points. I do agree though that the longer you can maintain a high power the better. Three minute intervals however should be done at even a higher effort than the 5 minute intervals.

Since at 5 minute intervals I was able to be at the high end of my VO2 Max zone, it makes me wonder if my threshold power is going up. That is the ultimate goal of all this training (whether long or short), so it’s a nice thing to ponder. This coming Saturday is the Camp Pendleton Sprint Triathlon, where I will be able to test my threshold during the 30K bike leg.