Interval Training

Leroy42

Hi Guys,

Have read a lot about 2x20 interval sessions on this board, and was just wondering what is the relationship in respect of duration and intensity.

For example, I did 2x10 mins intervals at 250watts yesterday, my first attempt and was really struggling to keep going towards the end of each, so on the 1st effort I changed from plan of 20 mins to 10.

My question is not about the power, I'm sure it is way off, but I have to start somewhere, but rather I am better doing 2x10 as above, or 2x20 at say 225 (or 200!) watts?

Obviously it would be better to move to 2x20 at 250 and go on from there, but I guess I'm asking where does to benefits start and end.

Apologies for the 'fuzzy' question.

ut_och_cykla

Well doing 2 x 10 is only half of 2x20. 20 is a 'magic' number because its convenient, and meassn you are working failry hard but still just aerobicly (or soem such explanation) 10 minutes means you are probably training other biological pathways and skills. The main point of 2 x20 is finding the right level to do just that! So doing 4 x 10 is okay but not the same as 2x 20.

Morpeth

The idea is that it is 2 X 20mins at your 1hr pace..., so if you can ride for 1hr at 230W, do two intervals of 230W.

so 90min session.

Warm up - 10mins at 150W -- 10 mins at 200W (20mins total)
Interval 1 - 20mins at 230W
Rest - 10 Mins at 200W
Interval 2 - 20mins at 230W
Cool down - 10mins at 200W -- 10 mins at 150W (20mins total)

If that is too hard change it around so the intervals are slightly lower and the rest is slightly lower but not too much lower than the interval.

250W any good? i am 65Kg and do 2x20 at 330W. Hope that helps.

Mike Willcox

Morpeth wrote:

The idea is that it is 2 X 20mins at your 1hr pace..., so if you can ride for 1hr at 230W, do two intervals of 230W.

so 90min session.

Warm up - 10mins at 150W -- 10 mins at 200W (20mins total)
Interval 1 - 20mins at 230W
Rest - 10 Mins at 200W
Interval 2 - 20mins at 230W
Cool down - 10mins at 200W -- 10 mins at 150W (20mins total)

If that is too hard change it around so the intervals are slightly lower and the rest is slightly lower but not too much lower than the interval.

250W any good? i am 65Kg and do 2x20 at 330W. Hope that helps.

LOL.

Performances on a turbo mean diddly squat. Can't you tell how good you are by what you do in races? Good Grief!

65 kgs with no brain.

Morpeth

Constructive reply there Mike, i was trying to help the guy structure a workout. Where is the problem with that?

Thats off an SRM and not a turbo (Leroy42 - turbo is still a good guide). My first season on the road (MTB background) so i cant comment on how i will get on in races... i however aspire to be as good as you Mike (are/were) as long as it doent turn me into a twat like it has you.

Two degrees and no brain,

Matt

Morpeth

It seems BR has censored my profanity and put fool in instead. It’s probably more accurate anyway.

Perhaps idiot or halfwit.

Mike Willcox

Morpeth wrote:

It seems BR has censored my profanity and put fool in instead. It’s probably more accurate anyway.

Perhaps idiot or halfwit.

At least I can profess to be a bit of an expert having won many races etc. etc.

IMO the definition of a fool is someone who makes prononuncements on what to do about something with little or no experience or real knowledge on the subject in hand. A bloody fool is someone who criticises someone else on a subject that have little or no experience or knowledge of the subject in hand. BF for short. Case m'lud

Morpeth

Ah mike, you have tripped over your own ego. Take a look back at my original post, the one before you suggested I have no brain.

My intention was to offer some assistance to Leroy given my understanding of how a 2 x 20 interval works. If my understanding is incorrect I would genuinely be pleased if someone corrected me and I could use this to improve my own methods.

You made no attempt to offer a constructive contribution, but rather waded in flashing your ego and presenting an opinion (my lack of a brain) that is apparently beyond question given your experience (which I don’t doubt or challenge).

If you feel this is a case of the blind leading the blind then please make a positive contribution. Do not refer to me as having ‘no brain’. You have demonstrated your clear lack of regard for my views without a fair justification.

Fool;

• One who is deficient in judgment, sense, or understanding.
• One who acts unwisely on a given occasion

You have demonstrated the above without question. Beautifully

So, I stand by calling you a fool, in response to you suggesting I have no brain. I am going to add dipstick for good measure.

Mike Willcox

No further comment. No need.

Morpeth

Agghh the high ground. Nice.

Clem

Well I found Morpeth's comments more helpful than Mike's sniping - most of us will never get anywhere near winning a race anyway!

Toks

Mike Willcox wrote:

Performances on a turbo mean diddly squat. Can't you tell how good you are by what you do in races? Good Grief!

65 kgs with no brain.

Oh I see getting bored are we Mike? There haven't been any 'rumbles' on here for a while so your backs arched and your ready to throwdown. I'm dissapointed mate, this is hardly a debate you could really sink your teeth into. Naughty naughty :roll: The OP posted a question specifically about 2 x 20's which lets be honest aren't in your training remit. The question was answered perfectly by Morpeth. Let it go Mike and find some bigger fish to fry

Mike Willcox

Toks wrote:

Mike Willcox wrote:

Performances on a turbo mean diddly squat. Can't you tell how good you are by what you do in races? Good Grief!

65 kgs with no brain.

Oh I see getting bored are we Mike. There haven't been any 'rumbles' on here for a while ready to throwdown.I'' dissapointed mate this is hardly a debate you could really sink your teeth into. Naughty naughty :roll: The OP posted a question specifically about 2 x 20's which lets be honest aren't in your remit. The question was answered perfectly by

Well we can all pretend that the exchange of posts on this thread between Morpeth and myself is what this is all about or we can seek the reality in the wider picture contained on the training forum. The choice is yours.

Morpeth

I am not sure i follow. In my 20... 21 posts on this forum have i wronged you in some way?

If so, we can discuss that (by PM if you like because i suspect most people arent interested)

Alex_Simmons/RST

Leroy42 wrote:

Hi Guys,

Have read a lot about 2x20 interval sessions on this board, and was just wondering what is the relationship in respect of duration and intensity.

For example, I did 2x10 mins intervals at 250watts yesterday, my first attempt and was really struggling to keep going towards the end of each, so on the 1st effort I changed from plan of 20 mins to 10.

My question is not about the power, I'm sure it is way off, but I have to start somewhere, but rather I am better doing 2x10 as above, or 2x20 at say 225 (or 200!) watts?

Obviously it would be better to move to 2x20 at 250 and go on from there, but I guess I'm asking where does to benefits start and end.

Apologies for the 'fuzzy' question.

The benefits we obtain from training are not confined to riding at discrete power levels/pace. It's all a continuum. It's really about riding sufficient total durations hard enough to elicit the desired adapatations.

Quite clearly there is a relationship between duration and intensity. The harder we ride, the shorter we can usually maintain that pace for. Seems reasonable enough.

As we get fitter, we can ride at a higher power/pace for the same durations. OK, that's easy to understand.

The relationship - in terms of maximal energy output vs time - is quite a linear one for predominantly aerobic riding durations over 1 minute and up to around an hour. For longer durations a few other practical factors come into play. For shorter durations (even up to 20 min) Anaerobic Work Capacity is also a factor.

If you are interested, then readup on the Monod & Scherrer Critical Power Model. (No, not Joe Friel's misuse of the term Critical Power).

Practically speaking, when using interval training as a time efficient manner to improve your aerobic fitness, then riding at power/pace levels than you can sustain* for the durations intended is what matters. Hence, you are short changing yourself if you ride a little too hard and don't get sufficient volume at these power/pace levels as a result.

* by sustain, I mean both in terms of that specific interval workout and also sustainable in that it doesn't significantly affect your ability to train on the following days.

Hence, if you are looking to do a 2 x 20, then you'll need to find the power/pace level at which you can manage to sustain in order to complete the intervals. If you couldn't sustain the power/pace, then you started too hard. Knock it back a notch next time.

If you got through them and they were easy, then knock it up a notch next time.

They are self regulating like that. A few sessions and you'll find the right level for you.

"Alls you can do is alls you can do"

BTW - 1 x 40; 2 x 20; 4 x 10 - it's all much of a muchness if there's not that much rest between efforts and the intensity and total duration is similar.

and of course there comes a time when shorter harder efforts make sense too. But that's a different discussion.

Tom Butcher

Just looking at Morpeth's suggested session - the extra 30 minutes at just 30 watts less than the 2*20s adds quite a bit to the session. I've been doing mine with only a 10 minute warm up gradually upping the intensity, then 5 minutes rest which is just easy spinning, more like half the power of the 20 minutes, and then my cool down is again just 5 minutes spinning an easy gear.

Morpeth

Tom Butcher wrote:

Just looking at Morpeth's suggested session - the extra 30 minutes at just 30 watts less than the 2*20s adds quite a bit to the session. I've been doing mine with only a 10 minute warm up gradually upping the intensity, then 5 minutes rest which is just easy spinning, more like half the power of the 20 minutes, and then my cool down is again just 5 minutes spinning an easy gear.

Interesting thought. I think you are right, if we remove the numbers and consider it a ratio, it’s finding the correct balance between hard (interval) and moderate/easy (Rest). I think it’s possible to add another phase within the workout that gives you 30mins moderate work without affecting the quality of the 20 min intervals. I guess its trial and error.

Alex_Simmons/RST

Morpeth wrote:

Interesting thought. I think you are right, if we remove the numbers and consider it a ratio, it’s finding the correct balance between hard (interval) and moderate/easy (Rest). I think it’s possible to add another phase within the workout that gives you 30mins moderate work without affecting the quality of the 20 min intervals. I guess its trial and error.

How much you can (should) do is to some extent determined by how much you have been doing.

If you do a longer than normal moderate to hard session but aren't used to it - you might find training the next day is compromised and reduces the overall training benefit.

It's what happens with the "weekend warrior syndrome" - do so much on the weekend that they are so trashed they can't train properly until Thursday. That's OK if you can't train mid week but is not optimal in the longer term.

Leroy42

Thanks for all the replies, but I fear that be starting this post I have unwittingly faciliated hostilies between Morpeth and Mike. There appears to be a lot of pent up frustration and anger, my advice......get on your bikes, find the nearest hill and blast away.

Seriously though, this was my first time (thankfully it's a while since I had to say that :oops: ) so I guess I went out to fast and found that I couldn't keep the effort going for the 20 mins. Morpeth's suggestion for the traiing is very good, and something I will try to work towards, but I the problem was touched on by Alex in that stiocking to the 20 mins may well get you through the session but leave you so drained that the next few days are a wash out.

My question was wether it is therefore better to run a shorter interval at desired output which then allows you to train over the follwoing days, or to run the full duration but with decreased output.

Again, thanks for the replies, I have a lot of work to do but the longest march starts with the first step and all that.

Morpeth

Leroy42 wrote:

My question was wether it is therefore better to run a shorter interval at desired output which then allows you to train over the follwoing days, or to run the full duration but with decreased output.

It sounds like you are misjudging the effort required in the interval.

1) I’d consider some general bike fitness, less focus on training programs and more on just going out and having a ride. This will give you a base and help you to feel comfortable just pootling around, if this base is not there the act of cycling is hard in itself without adding an interval.

2) The intention of the 2 X 20 is like you say to push but not so you can’t ride on following days. So yes, reduce the workload but keep a similar plan structure.

3) I think you need to find your limits by just riding a bike, that way its easier to determine when and how hard you need to be working.

Hope that’s clear.

Alex_Simmons/RST

Leroy42 wrote:

My question was wether it is therefore better to run a shorter interval at desired output which then allows you to train over the follwoing days, or to run the full duration but with decreased output.

Generally, I would pick the option that enables you to ride the full duration. There are exceptions but they would relate to the specific fitness attributes of individuals.

Riding at a slightly reduced power level/pace provides almost the same physiological benefits per minute of riding as riding harder but since it enables you to complete a far higher volume of training overall (in one session and across the week/block), for general aerobic fitness development, it is preferable to ride at that slightly easier level. Then every now and then do it harder for a change up.

Indeed riding at 90-95% of your best 20-min power is a great level to choose for 2 or 3 x 20min intervals.

As you get fitter, that baseline power level rises and so should the power level of your intervals.

As said before, there comes a time to up the intensity but that's not what you are seeking at this stage.