Understanding Intervals

Am I understanding how to train intervals properly?  There are so many calculators / training plans etc that seem conflicting and I wondered if this may be a good, or absoluetly awful training plan for intervals:

I'd like to train to improve my 10k time from 38:47 to 38:00 minutes.

For 38:00 minutes the average pace would have to be about 6:07 min/miles.

Therefore, would I do sets of intervals at 6:07 min/miles (or marginally faster), for lets say 3 minutes, with a 1 minute slow recovery, ensuring that the distance of the intervals covers the full 10k?

So to get to 38:00, would I just reduce the rest time a bit each training session until I can finally run a 10k in 38 minutes?

For a 10km there are probably two types of intervals you could usefully do: lactate threshold intervals at approx your 15km to half marathon race pace, and VO2 intervals at approx 95-98% of your max heart rate / heart rate reserve. If you're not sure what these equate to in mins per mile or 400m splits or whatever, put your times into this calculator to give an approximation for the splits you should be hitting, either on the track or the road: http://www.mcmillanrunning.com/calculator.

For the actual workouts, depending on your experience etc, you could try the following:

Week 1: 6x800 metres at current 5k pace, rest or jog slowly for 90 secs in between.

Week 2: (day 1) 4x400 metres at lactate threshold pace, broken up with 2 mins of slow jogging in between; (day 4) 5x600 metres at current 5k pace, rest or jog slowly for 60 secs in between.

Week 3: 5x1,200 metres at 2 secs per lap slower than your goal 10k pace; rest 75 secs in between.

Week 4: 4x600 metres at 5k pace, rest or jog slowly for 60 secs in between.

Those are by no means prescriptive but they are typical of the interval sessions you should consider... I'm sure if you buy a training book or use google you'll find much more useful material out there. It also goes without saying that you'll need to keep doing long runs, easy runs and basic speed as well!

Hope that helps.

Brilliant advice from mxb16.

Thank you for the advise mxb/Jamie.  I'd like to start learning the Science behind this so yes I will look out for some good books. 

I understand that after each set of these I should feel totally knackered.  But if at the end of the workout I still have something left then next time should I increase the speed a little or reduce the rest time? What I tend to currently do is just up the speed on the final interval until I'm completely done in!  I do 90% of my intervals on the treadmill and vary the incline frequently between 0.5% and 3% - do you think that's okay too? All my other runs, slow, hills, tempo etc are done outside cross country or road. Personally I find the treadmill harder than road because it's usually warm and stuffy in the gym so I think this tends to work for me as I like the gym environment.

Cheers

My inclination (although others may disagree) is to suggest that you don't push the pace until you feel totally knackered. For one, you risk making yourself too tired to do your other workouts. For another, you risk making your workout anaerobic rather than aerobic - obviously for a 10km you want to focus on your aerobic system, although some basic speed work (e.g. 12x 100m sprints) will help give you a "kick" towards the end.

Running on a treadmill is easier than running on the road or track, so set the incline to about 2% to offset this factor. 

Good luck!

I agree with mxb16, "totally knackered" is probably working a bit too hard.  Besides hampering performance in other sessions, you risk finishing off the interval session at something like race intensity, and what generally happens is that you lose control of your breathing, and your running form suffers.  You're much better off giving it 90% and "running through" the final rep with good form, feeling like you've got another rep in there if you need to.

W.r.t. intervals on the treadmill, you can do useful sessions but bear in mind that the faster you run, the easier it is compared to running outdoors, because you don't have to overcome wind resistance.  So banging out particular speeds on the treadmill may give you a false sense of your fitness, and not necessarily correspond to your true 10k pace.  For that, I like to do tempo intervals on the road or park, because it's so much easier to transfer that mentally to pacing an actual 10k race.

Thanks guys what you say is exacty what's happening, I do struggle with form and getting enough air in the final parts of my workout.

I did two 10 mile runs races over the last few months, the first one I didn't think I was properly prepared for it but was 3 minutes faster than last year (1:09 - consisting of lots of steep climbing).  Being pleased with the result I trained hard for my second 10 mile race a month later and was a minute slower than last year (1:07)!  I guess I'm learning the hard way! I will train up to about 90% from now on twice a week and try to taper properly before my next races.

I took up running 3 years ago thinking it was easy!