Power demands: Why not all riding is the same

One of the lessons I’m learning in my nascent racing career is just how vastly different the power demands are between different cycling scenarios. Having not been a life-long competitive athlete (the most I ever did was lunch-time football and beer-league soccer), my sporting background is all from steady-state endurance activities like leisurely cycling, hiking, or cross-country skiing.

But, having been tuned into cycling by Lance’s reign in the 1990s/2000s, I’ve always had the desire to race, even if I had no idea what the demands of racing would be.

With a power meter, I can now quantitatively see what I’ve learned through feel and experience over the past few years–namely, that there is a big difference between going at a steady, uncomfortable intensity for a long time, and going so hard you want to throw up for a couple hours. I’ll post some of my power files as an example.

*A quick note for those unfamiliar with power in cycling: power measures the force you apply to bike over a distance, and it’s how you measure your level of exertion while cycling. Exerting more power becomes more difficult to sustain for a longer period of time, (i.e relationship between power and the time one can exert that power is inverse). A key power benchmark is one’s “threshold”, which is the amount of power one can sustain for about an hour. Exertion above this level can only be maintained for a much shorter duration, while exertion below this level can be maintained for much longer than an hour.

Zone 1: “Active Recovery” (This is very easy spinning, and used when you’re recovering from intervals, or on a recovery ride)
Zone 2: “Endurance” (An “all day” pace)Zone 3: “Tempo” (The pace of a fast group ride, where you have to exert effort, but you’re not going cross-eyed yet; you can talk, but it takes a lot of effort)
Zone 4: “Threshold” (What you could hold for an hour, if you really tried; in practice, even 20 minutes at this intensity hurts)
Zone 5: “VO2Max” (An intensity you can only hold for about 10 minutes; your breathing is very ragged at this point)
Zone 6: “Anaerobic capacity” (Very hard effort that you can maintain for less than five minutes; you can barely breathe, and if you’re talking, it’s usually cursing)
Zone 7: “Neuromuscular power” (Very short, high-intensity efforts like standing starts, attacking, and sprinting)

Power file 1: A brisk group ride

cochranegrp power

This file is from a lively three-hour group ride with some fast friends, and included two hills that we attacked hard (COP and Cochrane). Spent some time at higher intensity levels (Zones 4 and above), but not that much. Came back from this feeling tired, but good.

Power file 2: “Easy” road race

velocity power

This file is from the Velocity Road Race in Edmonton. The race lasted 1:49, which is shorter than the group ride, but you can see how much more time I spent at the higher intensity levels. This race was on a flat course, so the time at a higher intensity levels is from moving up in the pack without a draft, responding to surges, and accelerating out of turns. While I still spent a lot of time in Z1 (likely from coasting while in the pack), I spent less time in Z2 and 3, since I was either “sitting in” behind a wheel and taking it easy, or responding to changes in pace.

The other thing about this race is that I spent most of my energy in the first 20 minutes moving from the back of the pack into the front third, and in the final 10 minutes, where I fought for position and sprinted for the finish. For the rest of the race, I just sat in and enjoyed the ride.

In total, I spent 45% of the race at threshold power or above, and 36% of it at VO2Max power or above at Velocity.

Power file 3: “Hard” road race

RMSR power

This is from the Rundle Mountain Road Race in Canmore–a hilly and difficult race. I spent even more time at the highest intensity levels. Because of how hilly this course is, drafting has less of an effect, and if you want to stay at the front, you had to be able to climb with the strongest. Unlike Velocity, I wanted to be near the front for the entire race rather than taking my chances climbing slowly and not having anyone to work with to get back to the front. So, I tried to keep pace with the best climbers, and I constantly worked to stay in a good position. This meant I could respond when the decisive move came (even if my response backfired spectacularly).

Comparing the two courses to each other–they’re both around 65km and I averaged 37km/h for both. The difference is that Velocity only had 200m of total elevation gain, whereas Canmore had four times that amount.

Power file 4: A crit

Rundle crit power

Criteriums are a race format unique to North America, and are cycling’s version of Formula One. They’re held on closed city streets and use short courses (~1km in length) with a lot of turns. Races are short (varying from 30 mins to one hour, depending on the level of racing), and are very spectator-friendly.

Because of all of the turns, there is much deceleration and acceleration that happens in the race. You have to sprint out of each corner, lest you get dropped from the pack. Thus, it’s no surprise that you spend the most time in Zone 7 in a crit (or at least I do, because I’m trying to hang on to the back, where the accelerations are even worse than at the front).

Summary Table

Ride Type Time @ Z4+ Time @ Z5+ Time @ Z6+
Hard group ride 39% 28% 17%
Easy RR (Velocity) 45% 36% 29%
Hard RR (Rundle) 52% 41% 32%
Criterium 65% 57% 51%

What I learned

One of my goals this spring was raising my threshold, and I would do at least one threshold or sweet-spot (high tempo zone) workout a week to do just that. The issue with that is there aren’t that many racing situations in Alberta where riding my threshold would put me in a winning position. Being 5’2″ and 120lbs (at least on a good day), having a high threshold would help me ride away on a long (20min+) climb, but would still make me a deadweight in a breakaway because bigger guys are way more powerful, but not that much less aerodynamic than little guys. In Alberta’s flat courses, the guys I’ve seen win tend to be great sprinters supported by a strong team, or breakaway artists with huge engines.

(Yes, I know I could HTFU and train more to get my threshold up to 300W, but that’s a little difficult working two jobs, seven days a week.)

What I did in the lead-up to Rundle is less threshold training and more sessions doing VO2Max and anaerobic capacity work. Those power levels are the ones used for the make-or-break moves that decide races. Though I failed to get a good result at Rundle, I was foiled more by my stomach than my legs, and I was consistently in the right place at the right time, which provides some affirmation that my training has been paying off.

For my friends who are looking to race, your takeaway should be to incorporate intervals into your training, and to work on generating higher 1-5 minute peak power and being able to repeat that over and over and over and over and over until you can’t.

The remaining two road races this season (Bowness and JLap) are both flatish courses that, if you’re not in the breakaway, degenerate into “sit-n-kick sandbag festivals,” so I’ll likely play the same hand I played in Velocity. But, the Banff GranFondo will provide a chance to see if my improved ability to ride at higher intensity levels will mean I can stay with the main pack for the entire race.

2016 Update:

Both Bowness and JLap were less flat than I thought. Bowness featured a short-but-steep 5-minute power climb, and JLap had a bunch of rollers. In both cases, they produced a selection, with JLap reducing the finishing field to about 20, and Bowness, down to less than 10.

I can definitely say that the work I did on VO2Max-level efforts, recovery from such efforts, and explosiveness helped me to top-10 placings in both races.


About jbsantos
Polling, politics, PR and outdoor pursuits.

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