I've been using a pt for about a month. Its over now, no more power to look at. There is a ton of info you can get from training with hr/power if you have the time to analyze it. I don't.
Its much easier to do what Myerson does.
"On tap: sprint for 15 seconds, coast for 15 seconds, repeat 40 times, x 2. @AthensTwilight is coming..."
This doesn't require any computer. Just keep your head up, watch the road, and pedal super hard. If you don't feel like throwing up after 6 of these, you aren't doing it right.
When people say, "but I'm not a sprinter." I want to say, neither is anyone else you are racing against. If you are a sprinter, you probably went from a 5 to a 2 in 6 months...if you are a true sprinter. Everyone else, 98% of us are not.
My point, is that even though you are not a sprinter, you should still learn to sprint, or train a little with sprinting.
Since you suck so bad at it, you have a ton of room for improvement.
I've seen some horrible sprints. Awful.
Fact is, if you are in a race, the guys you are racing against, probably can't sprint much better than you can. That's why you are in the category that you are.
Watch cav here. Chin is on the stem, ass in the air, perfect pedaling stroke, big gear, mouth open breathing, in the drops, head up and low.
I do recommend the 15/15 interval. Maybe after 5-10 times your legs are toast. Here is where you need to focus on form, not power. Stay low, breath properly, and pedal efficiently. When you pedal, it should be the worst pain imaginable that you can inflict on yourself. Big gear, full pedal rotation, using every ounce of energy you have to put as much power into the pedals while staying as low (read aero) as you can, while breathing and looking ahead.
So you are 140lbs, consider yourself a climber. You get in the move, 4 of you are away on a hilly 50 mile road race. Now what? You gonna out climb the other climbers?