'work' time at differing paces
This came up on the dashboard today, and it also occured to me in the past, so I figure I mine as well post and see what the general basis is:
Lets take todays OS run workout for example - 2 x 2 miles @ TP. Now take two athletes, Bob and Joe. Bob has a VDOT of 41, so his threshold pace is 8:02 min/mile (lets round to 8 min/mile to make it easy). Joe has a VDOT of 58, so his threshold pace is 6:04 min/mile. Both of those VDOT values are certainly within the realm of an age group athlete, so I think they represent a good sample.
Bob does his workout, and ends up spending a total of ~32 minutes @ TP (4 miles * 8 min/mile). Joe, who is following the same plan, does his workout and ends up spendint a total of ~24 minutes @ TP (4 miles * 6 min/mile). That is a 30% difference in time spent @ TP - which is not insignificant. Isn't there an inherent discrepency between the training effect that Bob recieves VS what Joe receives? Shouldn't Joe be doing an extra 1.3 miles to get to the same 32 minutes @ TP?
Work is defined as force through a distance - so assuming both athletes weigh the same (so that the force component is equivalent), and since they traverse the same distance during their sets - they do the same amount of work. Now, their power is different, because power is work over time, and since Joe does the same amount of work but in a shorter amount of time, he is producing more power.
So I guess the question is: what is the more critical component to making us faster - time at a faster pace, or the power produced? Because if it is time, then the faster athlete gets short-changed since the plans are based on distance and work remains the same. On the other hand, if the real goal is to produce more power - then that helps equate things a bit, but that begs the question of why bike workouts are based on time, regardless of FTP?
Comments
Ryan- you make a very good point. Although I am new to EN, other plans that I've used to train with in the past almost always associate a fixed time frame when training for the run and bike. The swim was usually a fixed distance.
But, if I'm not mistaken, my OS workout for today was a fixed time for run, with a MS that was a fixed distance. So, in essence, regardless of your speed on the MS, you would still be putting in the same overall time running and the same effort.
To clarify - I'm speaking only of the main set where today's workout (the adv plan) was 2 x 2 miles @ TP. The only way two runers would be doing that main set in the same amount of time would be if they also run at the same pace.
One thing your point brings up is that for a workout with a time goal (not a pace one), the faster runner will do more work because they will have traversed a longer distance overall.
I would guess that this has to do with overall fatigue, meaning the stress a body experiences from being out "training" for more than 2 and a half hours, but if you're going to be out there much much longer on race day.....does your body need to build that endurance too?
I'm not looking to run further, as I'm more than fine with a 2.5 hour longest run, but some people may wonder about this, so I thought I'd add it to the conversation.
Yeah I suppose it does make for a larger gap come race day - but I guess the other side of the coin is that race day is a one time thing, where you have much more bandwidth for recovery afterwards, as opposed to when following a plan leading up to the event, where you still have workouts scheduled in the near future.
In the case of bike wkos, the intervals are time based at particular relative intensity (eg Z4 = 0.95 to 1.0 of FTP etc) — meaning the training dose is minutes @ a set percentage of FTP.
As you point out, if running Z4 intervals were designed on the same basis as the bike wkos, then they would be intervals based at a particular percentage of your Threshold Pace.
Given they aren't designed that way, the reason must be based of the higher recovery cost of running compared to cycling (as Kori suggests) — therefore limiting the Z4 running to a given distance rather than time as is the case with the bike.
But what incurs the higher recovery cost of running - the time, or the distance? Based on Daniels suggested maximum of 150 minutes for a long run, that would seem to indicate that it is time based, not distance. And how is Z4 recovery for someone at a VDOT of 38 different than someone with a VDOT of 55, if they've done that Z4 work for the same amount of time?
The discrepancy obviously comes from the fact that a threshold workout based on distance means more time @ Z4 for the person with the lower VDOT. The only way I can see the two levels of stress being equal is if the faster pace results in more pounding force that the body of the person with the higher VDOT must absorb. But that idea is shot down because Daniels doesn't specify maximum long run times based on VDOT - he does it based on the clock.
@Kori- I had that same question as I trained for IMFL as a super-slow runner. My longest run was 13 miles prior to IMFL. Crazy, huh? But I followed the plan and I was fine. i think the philosophy on that is that someone as slow as me doesn't REALLY expect to run the entire 26.2 of an IM (correct!) so no need to run anywhere close to that. I can't say what percentage I actually ran... Somewhere more than 50% but less than 80%, so the 13 mile long run was fine. The place where a longer run would have come in handy is the fact that I got major blisters on the bottoms of my feet at mile 18-ish that I have never experienced before which slowed me down way more than any of my other body parts!
But back to Ryan's original question.... I often feel like I'm not getting as much training in as faster folks because based on time, I'm doing the same work but getting in 5mph vs. 7,8+. But in terms of effort, I have no doubt my 10min/mile pace is just as hard for me as someone else's 6:30 pace!
I would guess that if you test out at a 41 VDOT, you are doing the intermediate plan, which has shorter run intervals.
There is an argument for doing run and swim intervals based on time, not distance. In the world of TSS, if two people are both doing run intervals by distance, and both doing the same "zone" effort, then the one running for more time will have a higher TSS. I think the primary reason for basing run and swim intervals on distance and not time is that for many, it's easier to measure the distance (pool length, track or road distance) than time (constantly looking at your watch or pre-programming intervals by time).
And, for each Zone, there will be an ideal time spent per interval which maximizes the training value. For "TP" or Z4 type runs, that's about 6-8 minutes, which is a mile for many of us. For those with very high or very low VDOTs, they would be better served adding or subtracting distance respectively to get the ideal training dose. For the rest of us, going for 6:30 vs 8 minutes is pretty much the same thing. And, arguably, the lower your VDOT, the more you might want to err on the side of doing a bit more work, up to an 8 minute interval for that TP/Z4 stuff. Same thing applies to swimming, just divide the distance by 1/4: 400 yds/meters swimming pretty much = 1 mile/1600 meters running. And if you are spending more than 8 minutes doing those 400s, you could safely decrease the distance of each interval to stay within the 6-8 minute range.
Ideal rest interval length is another topic I'll stay away from here.
Michael makes a good point about using different plans and getting closer to the same training effect ased on that.
The only logical counterargument is that if you are training for a specific race distance (which we all are, at some level), then having efforts that stretch over certain fractions of that distance could be argued for.