Originally Posted by DNAtsol .
...Am I thinking about this right?...
No, not really.
Focus on sustained intensity first, whether you measure that via HR, Perceived Exertion (RPE) or power isn't as important as the goal of increasing the intensity you can sustain for long durations as in 10 to 30 minutes or longer per effort. If you do that your times for long and short rides will decrease.
Cadence is at best secondary to that goal and can be misleading especially if you estimate intensity from HR as very high cadences tend to drive HR very high even when the absolute intensity (i.e. power) is not that high. Try spinning 160+ rpm on a trainer with the resistance unit disabled and not touching the rear wheel, do that for 10 or more minutes and your HR will climb even at the very low power you're actually producing in that situation.
Training for specific cadence has the most relevance for addressing particular racing needs. For instance if a rider tends to diesel away all day at say 80 rpm that might work great in time trials but put him at a competitive disadvantage in very dynamic racing situations like the frequent high power accelerations out of criterium corners or an aggressive and punchy road race where leg speed and the ability to sustain power in lighter gears is very useful so that the rider can respond to the frequent attacks with leg speed instead of brute force. Similarly leg speed is a limiter for many sprinters and some high cadence work can add a lot of snap and higher top speeds for these folks.
Those are good reasons to do specific cadence work as they address specific racing needs but from a general physiology and training development standpoint cadence should not be the primary training goal. Sure it's useful to have a wide range of useable cadences that feel natural to help you deal with different situations and to avoid grinding big gears all the time but neither high nor low cadence training in and of itself assures appropriate training stress. If you had a power meter you would focus on sustained power as the best proxy for training intensity, lacking that you can use HR if the efforts are long enough. Remember HR lag and the time it takes for your HR to catch up with hard efforts, for instance, in the case of a steady 20 minute Threshold interval it typically takes six to seven minutes for HR to reach the average for the 20 minute interval. Trying to pace or gauge intensity by HR in those early minutes while it is still rising leads to going out too hard and inevitably fading towards the end of the effort. So HR makes the most sense for long efforts in the 10+ minute range and it still requires some patience to let the HR numbers catch up with your efforts.
If your hills are steep and can be climbed in less than 10 minutes each then you either want to use them for VO2 Max work ( typically 3 to 6 minute interval repeats) or if possible you want to use all your gears to continue applying power and pedal pressure on the descents so you can stretch these efforts up to 10, 20, 30 minutes or beyond. If that's not possible then try to find some steadier, longer climbs or open flatter roads or even parking lots, or industrial parks where you can do laps to sustain longer efforts on your Threshold and Tempo training days. If none of those options are available then there's always the indoor trainer for sustained Threshold and high Tempo level work but one way or another it really pays to do some days of sustained high end work racking up forty minutes to an hour of solid near Threshold work in the form of 2x20s, 3x20s, 4x15s, 1x60s or whatever style of Threshold interval you prefer and fits your available training route options.
Bottom line, if you want to go faster in endurance events then you want to increase your sustainable power across the durations of interest. You don't need a power meter to accomplish that goal but you do want to ride sustained efforts at moderate to high intensity. What cadence you sustain during those efforts may be chosen to satisfy some other training goal (like the ability to sustain power at 90+ rpm in preparation for more dynamic mass start racing) but it's not the primary thing you should focus on. HR can work as a feedback and workout quality assessment tool but it has limitations in terms of shorter efforts, lag time and drift in longer efforts. Good old RPE and paying attention to feeling, breathing rate and using that to assess intensity has worked for generations of top level cyclists and shouldn't be ignored as a very useful way to gauge intensity while training.
Good information here: http://home.trainingpeaks.com/power411.aspx
Yeah, it's written from a power perspective but the training goals and methods are the same regardless of the metrics you use to assess workout intensity. Check out the link on 'power levels' for a rough mapping to HR levels relative to Threshold HR which BTW is NOT max HR for the reasons given in those links.
You might also search the web for info on SST or Sweet Spot Training, again most of it is described in power terms but all the ideas apply just as well to someone tracking training via HR or RPE.
Good luck,
-Dave
