The best approach to L5 intervals

[bgoetz]

Ok, at this point in my training I have 1 day devoted to L5 intervals. Initially I wanted to start with 5min on 5min off and increase the number of intervals each week, pretty simple. For some reason I was thinking that a good target for power would be my 5min max (currently 417watts), pretty stupid. I did the 1st interval today, hitting 410watts avg power, took my 5min rest and then blew up after 2min with an avg power of 385watts (who would have thought /img/vbsmilies/smilies/rolleyes.gif). Took another 5min rest and was able to make it 4.5min at around 385watts, but it was insanely painful.

From there I decided that it was ridiculous to think that I could target my max 5min and expect to come even close on subsequent intervals, really not sure why the thought did not occur to me prior. I then decided to shorten the interval length to 90seconds targeting 400watts and taking a 90 second break in between. I was able to complete 2 of these at over 400watts, 2 at around 380watts, and on the 5th one I decided I had enough and only hit 375watts.

I think if I just went with the 90 seconds on 90 seconds off I could do 5-6 at close to my 5min max, then take a 10min break and do 5 or 6 more. If I am going to do something at around the 5min range I am going to need to back my expectations down and target maybe 375watts for 4-5 sets, or REALLY extend the workout and have a much longer recovery between intervals.

So, I guess my question is would it be better to target a higher wattage, shorter duration, and more intervals OR lower wattage, longer duration, and less intervals OR do something closer to my max and just extend the recovery intervals. At this point in my training I have a day devoted towards longer intervals close to my LT and then another day spent racing or doing a fast group ride, so there is no option of doing more than 1 of the options. My plan for 3-4weeks out is to shorten the short intervals even more and target something closer to my 1min max, I am just trying to hold off on something that intense until it gets closer to my planned peak.

Suggestions??

 

[swampy1970]

As you said, trying to pop off consecutive "best efforts" is a bit much but it's a learning experience - no loss really.

I'd consider doing a couple of 5 minute efforts and some shorter, say 3 minute efforts done at a slightly higher wattage. I'd also consider not having a constrained rest period initially - do the effort and take 10 minutes of easy pedaling, or more, if needs be. If you want to train "lactate tolerance" for want of a better term then shorter, very aggressive intervals with an equally short rest period may be better - but trying to do quality L5 when your legs are blocked from the last big effort may not be optimum.

Don't forget that when you're racing you're also likely doing lots of L5 and you can use races that you're not targeting as training - doing L5 efforts just for the heck of it off the front for seemingly no reason can have good consequences or at the worst, you get some really good training. Add to that you'll likely do higher quality work when somewhat motivated in a race and you get to find who all the lemmings are at races.

I don't know what the general consensus is but I used to find that short intervals of 5 minutes or less, done a couple of times per week took about 6 to 8 weeks to really kick in with noticeable benefits coming a couple of weeks after that.

 

[doctorSpoc]

Originally Posted by bgoetz .

Ok, at this point in my training I have 1 day devoted to L5 intervals. Initially I wanted to start with 5min on 5min off and increase the number of intervals each week, pretty simple. For some reason I was thinking that a good target for power would be my 5min max (currently 417watts), pretty stupid. I did the 1st interval today, hitting 410watts avg power, took my 5min rest and then blew up after 2min with an avg power of 385watts (who would have thought /img/vbsmilies/smilies/rolleyes.gif). Took another 5min rest and was able to make it 4.5min at around 385watts, but it was insanely painful.

From there I decided that it was ridiculous to think that I could target my max 5min and expect to come even close on subsequent intervals, really not sure why the thought did not occur to me prior. I then decided to shorten the interval length to 90seconds targeting 400watts and taking a 90 second break in between. I was able to complete 2 of these at over 400watts, 2 at around 380watts, and on the 5th one I decided I had enough and only hit 375watts.

I think if I just went with the 90 seconds on 90 seconds off I could do 5-6 at close to my 5min max, then take a 10min break and do 5 or 6 more. If I am going to do something at around the 5min range I am going to need to back my expectations down and target maybe 375watts for 4-5 sets, or REALLY extend the workout and have a much longer recovery between intervals.

So, I guess my question is would it be better to target a higher wattage, shorter duration, and more intervals OR lower wattage, longer duration, and less intervals OR do something closer to my max and just extend the recovery intervals. At this point in my training I have a day devoted towards longer intervals close to my LT and then another day spent racing or doing a fast group ride, so there is no option of doing more than 1 of the options. My plan for 3-4weeks out is to shorten the short intervals even more and target something closer to my 1min max, I am just trying to hold off on something that intense until it gets closer to my planned peak.

Suggestions??

I'm with Swampy in that I do these if I'm not racing.. or usually before I open the racing season or if I have a lull in racing in season..

the point of these is for them to REALLY hurt... i tend to do 3mins with 3-4min recovery... the last minute of that 3mins you should be in quite bit of excruciating pain.. don't sweat the actual value of power (just try to be in you zone).. find a power around which you can barely finish the interval because of that pain.. successive intervals will get harder and harder earlier so you might want to temper your first few with that in mind.. after a couple of times doing it you will know what kind of power to use... I like to do two sets of 3 or 4 with about 20 - 30mins between sets.. sometimes i wimp out at 1 set of 4 though /img/vbsmilies/smilies/smile.gif... these hurt.. A LOT.. but that's how you know you are doing them right...

in my opinion it's better to do short, higher intensity since if you go to lower intensity you intervals will start to turn into Threshold intervals at the end of a set because your power will drop too much.. that's why I go with the 3mins..

 

[hrumpole]

+1 for this. I once missed a turn on a route that I've ridden dozens of times and ended up adding a half-hour b/c I was so oxygen deprived doing 3 on 3 off. You'll know when you're out of steam; it will feel like your legs are made of cement.

Originally Posted by doctorSpoc .



I'm with Swampy in that I do these if I'm not racing.. or usually before I open the racing season or if I have a lull in racing in season..

the point of these is for them to REALLY hurt... i tend to do 3mins with 3-4min recovery... the last minute of that 3mins you should be in quite bit of excruciating pain.. don't sweat the actual value of power (just try to be in you zone).. find a power around which you can barely finish the interval because of that pain.. successive intervals will get harder and harder earlier so you might want to temper your first few with that in mind.. after a couple of times doing it you will know what kind of power to use... I like to do two sets of 3 or 4 with about 20 - 30mins between sets.. sometimes i wimp out at 1 set of 4 though /img/vbsmilies/smilies/smile.gif... these hurt.. A LOT.. but that's how you know you are doing them right...

in my opinion it's better to do short, higher intensity since if you go to lower intensity you intervals will start to turn into Threshold intervals at the end of a set because your power will drop too much.. that's why I go with the 3mins..

 

[swampy1970]

I don't think you'll ever be deprived of oxygen because you did L5 intervals...

... but if your legs only feel like they're cement then you need to go harder. When your arms and shoulders feel like cemet, your legs have been waxed with napalm and the musty taste of dead lung fills your mouth... Either that or vomit.

 

[bgoetz]

Yeah, I am good on the PE of L5 intervals, my shoulders do start to ache, sometimes I actually wonder if I am having a heart attack, lol. I guess I was a bit suprised at how hard it was to do a max effort and then expect more from my legs, those big #s don't seem as special when you can only do it once, but I think with a couple of weeks of solid work I will get it back. Since most of my L5 work in a race/fast group ride is shorter duration I may start with some 3x3s at my 5min max, maybe do 4 to 5 sets rest and then try some more or maybe a few 90x90. I will slowly try to work to get to the point where I can turn out sucessive 5x5s at 400+ watts, but it will be a slower process than I had originally planned. Although my guess is that once I can turn out sucessive 5min intervals at close to my "max" power, it will no longer be my max power.

 

[swampy1970]

It'll take more than a couple of weeks to repeatedly hit what is now your max 5 minutes number - I'd say at least 10... and that's from many years of painful experience, thankfully not recently.

 

[hrumpole]

Dunno--could have been dehydration,but it was one of those things where you literally could barely see. I don't think I could have done simple math.

 

[An old Guy]

Pick your power output and hold it until your heart rate gets high enough. Rest until your heart rate recovers.

If your power intervals are too long, increase your power. If too short, decrease your power. If the rest intervals are too long, reduce your power heart rate target. If too short; increase your target.

Really not that hard to train with power.

 

[bgoetz]

Originally Posted by An old Guy .

Pick your power output and hold it until your heart rate gets high enough. Rest until your heart rate recovers.

If your power intervals are too long, increase your power. If too short, decrease your power. If the rest intervals are too long, reduce your power heart rate target. If too short; increase your target.

Really not that hard to train with power.

You have obviously never spent much time doing L5 intervals, at least not in succession. If I go by HR my average HR over 5min for my 410watt interval was 176 bpm, my average HR for subsequent intervals was only low 170s (171-173). I physically do not have the ability to repeat the effort HR or power. Simply holding x watts longer will do nothing, my HR will eventually stall out at a lower HR until I don't have the legs to continue and then my HR will start to fall. The fact that you have never experienced anything like this is yet another reason I don't even think you as much as own a bike and therefore hold your opinion in the same regard as my 8 year old brother's opinion on the matter.

And my response to you is not to fuel additional debate, but to eliminate miss information from what could be a useful thread to others on this forum. I therefore respectfully request that you don't add any additional responses/information to my thread, I would really like to keep this thread as a useful informative thread for others.

 

[An old Guy]

L5 is anywhere from 105-120% FTP (average power). It appears you confused your 5 minute max with L5.

---

I am old. I know how I need to train.

I do L5 intervals most rides: 30 minutes of L5 intervals - let my heart rate rise to LT; hold it until I lose interest; L4 until my heart rate falls enough; repeat. Take a break. Do 30 minutes more.

I do mine. You do yours.

---

Don't ask a question, insult people who respond, and then demand that they keep off "your" thread.

 

[bgoetz]

Originally Posted by An old Guy .

L5 is anywhere from 105-120% FTP (average power). It appears you confused your 5 minute max with L5.

---

I am old. I know how I need to train.

I do L5 intervals most rides: 30 minutes of L5 intervals - let my heart rate rise to LT; hold it until I lose interest; L4 until my heart rate falls enough; repeat. Take a break. Do 30 minutes more.

I do mine. You do yours.

---

Don't ask a question, insult people who respond, and then demand that they keep off "your" thread.

My thread was not about how do do an L5 interval, it was about doing L5 intervals at close to my 5min max, so no I am not confused. Second I never demanded that you keep off my thread, I respectfully asked that you keep off my thread, because you can't look at a single thread on this forum without having to wade through piles of the **** that you spew, and I wanted to avoid having this as yet another thread. Guess it is too late for that now......

 

[SteveI]

Originally Posted by bgoetz .
You have obviously never spent much time doing L5 intervals, at least not in succession. If I go by HR my average HR over 5min for my 410watt interval was 176 bpm, my average HR for subsequent intervals was only low 170s (171-173). I physically do not have the ability to repeat the effort HR or power. Simply holding x watts longer will do nothing, my HR will eventually stall out at a lower HR until I don't have the legs to continue and then my HR will start to fall. The fact that you have never experienced anything like this is yet another reason I don't even think you as much as own a bike and therefore hold your opinion in the same regard as my 8 year old brother's opinion on the matter.

In this particular instance, I actually thought AoG's advice wasn't a bad way to approach an L5 set. You experienced what you did because you did the first rep far too hard. I do my L5 intervals as 6 x 5 with 2 mins recovery, and I always reckon that if I have chosen the right power, my peak HR will be very slightly higher each interval, and pretty much maxed out in the final interval where it should need basically an absolute max effort to repeat the same power as the earlier intervals. So how I home in on the right power is by keeping the structure fixed, but adjusting the power based on previous sessions. AoG was describing a way to adjust both the structure and the power, and it was useful food for thought IMO.

 

[bgoetz]

Yeah, but on an interval as long as 5min, my power/HR are pretty much reflective of each other. What I think you and OG are saying is your HR and PE seem to be more reflective, which has not been my experience.

The reason I brought the 5min max into the topic is because in my mind intervals should be as close to max power as possible and 5min is about as long as is useful for an L5 interval, any longer and you start getting into LT interval range. The key is whatever power you choose, they have to be repeatable. As my original post intended to point out was that shooting for a max effort on the 1st go is certainly not repeatable. So my question was not really about how to pace myself, but what is better longer intervals at lower power or shorter intervals at higher power. I just used the 5min max in the discussion as a fixed point to make the discussion a bit easier, it also happens that my 5min max seems to be a more repeatable # on a 90sec L5 interval.

It sounds like what you have found is a pretty solid # that is both repetitive and puts you at your max PE by the last interval, which is great. Although that leads to another debate as to if you would be better starting with a higher wattage and just basically doing max PE each interval over a given time. So instead of starting at say 385watts and doing 385watts for 5 sets reaching max PE by the last set are you better starting at 415watts and doing max PE each set, but only maybe getting out 4 sets before you cannot hold L5 power? Option A will train your body to put out repetitive efforts of similar power, while option B will allow you to train your body to put out more power and IMO will put you through more suffering. I don't think there is a right or wrong, just two different approaches.

But again my original question was shorter intervals more power or longer intervals less power, I guess including the 5min # as a fixed # to discuss things off of may have confused things.

 

[SteveI]

Originally Posted by bgoetz .

But again my original question was shorter intervals more power or longer intervals less power, I guess including the 5min # as a fixed # to discuss things off of may have confused things.

For that particular question, it depends what your objectives are. I find anything shorter than 5 mins has a substantial impact on AWC and doesn't translate well into improved FTP. As my personal interest is TTs, my only objective in doing VO2max intervals is to lift the ceiling on my FTP, I don't have much interest in increasing my AWC. So while I saw good improvement in the power I could manage for 3 and 4 minute intervals with longer rest, it was only when I moved to 5 minute intervals with shorter rest that I started to see the gains really translating into improved FTP. I'm currently managing the same power for 6 x 5 mins with 2 mins rest as I was doing for 4 x 3 mins with 3 mins rest back in November. But having said that, I haven't seen any progress in my 6 x 5 power for the last 6 weeks, so I might try shifting back to shorter intervals to see if a spell of doing those at higher power shakes things up a bit.

I've actually based my training on these zones to some extent:
http://home.trainingpeaks.com/articles/running/pace-zone-index-details.aspx
So I figure that 5 minute reps done at the same power as you could do for a one off max effort 8 mins can't be too far off the mark.

 

[swampy1970]

Originally Posted by bgoetz .

Yeah, I am good on the PE of L5 intervals, my shoulders do start to ache, sometimes I actually wonder if I am having a heart attack, lol. I guess I was a bit suprised at how hard it was to do a max effort and then expect more from my legs, those big #s don't seem as special when you can only do it once, but I think with a couple of weeks of solid work I will get it back. Since most of my L5 work in a race/fast group ride is shorter duration I may start with some 3x3s at my 5min max, maybe do 4 to 5 sets rest and then try some more or maybe a few 90x90. I will slowly try to work to get to the point where I can turn out sucessive 5x5s at 400+ watts, but it will be a slower process than I had originally planned. Although my guess is that once I can turn out sucessive 5min intervals at close to my "max" power, it will no longer be my max power.

Don't confuse doing intervals to train for power and intervals to help you deal with tolerating short periods of recovery.

If you want to increase power in a more effective way - you will need a longer recovery period, most likely longer than just a few minutes.

If you want to increase your "lactate tolerance" then come up with your predefined set of intervals, probably longer efforts to start with and shorter ones towards the end and figure out what you can hold during those efforts. It will NOT be you max effort.

 

[An old Guy]

Originally Posted by bgoetz .

Yeah, but on an interval as long as 5min, my power/HR are pretty much reflective of each other. What I think you and OG are saying is your HR and PE seem to be more reflective, which has not been my experience.

The reason I brought the 5min max into the topic is because in my mind intervals should be as close to max power as possible and 5min is about as long as is useful for an L5 interval, any longer and you start getting into LT interval range. The key is whatever power you choose, they have to be repeatable. As my original post intended to point out was that shooting for a max effort on the 1st go is certainly not repeatable. So my question was not really about how to pace myself, but what is better longer intervals at lower power or shorter intervals at higher power. I just used the 5min max in the discussion as a fixed point to make the discussion a bit easier, it also happens that my 5min max seems to be a more repeatable # on a 90sec L5 interval.

It sounds like what you have found is a pretty solid # that is both repetitive and puts you at your max PE by the last interval, which is great. Although that leads to another debate as to if you would be better starting with a higher wattage and just basically doing max PE each interval over a given time. So instead of starting at say 385watts and doing 385watts for 5 sets reaching max PE by the last set are you better starting at 415watts and doing max PE each set, but only maybe getting out 4 sets before you cannot hold L5 power? Option A will train your body to put out repetitive efforts of similar power, while option B will allow you to train your body to put out more power and IMO will put you through more suffering. I don't think there is a right or wrong, just two different approaches.

But again my original question was shorter intervals more power or longer intervals less power, I guess including the 5min # as a fixed # to discuss things off of may have confused things.

I will try to be more helpful. If you wrote the 415w and 385w as percentages of FTP or wrote L5 in terms of watts, everyone would have a clearer idea of how to help you.

If your FTP is about 345w the 415w is about 120% FTP and 385w is about 110% of FTP. Both are L5 intervals. It does not matter much if you start out with 415w and drop down to 385w over the intervals or if you just pick a L5 power output and target that for the intervals.

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About HR and PE: I use heart rate as my clock. You go for 5 minutes and rest for some time period. I go until my heart rate rises to a certain level and rest until it drops. It is just easier for me.