OK, will give 4x1600m at 6.20 pace a try within the next 10 days (post-mara legs still a bit heavy this week for speed work) and see how it goes.
Re tempo, I was doing my LT sessions in marathon training at about 6.45/mile pace so will stick with that for now.
Best of luck with your own goals - I would be biting my knuckles in irritation if I was on for a sub-40 and got sent the wrong way. At least that isn't an issue at Battersea Park!
4 x 1600m would be a very good session. One week out from the race I try a 4 mile time trial at race pace. I wouldn't keep the recovery between each rep too long, 2 minutes max.......and I'd try and reduce the recoveries as the weeks pass.
As for your tempo; 20 secs above 10k race pace sounds about right.
Fair point. But one of the reasons I like these forums is because those sort of people are relatively rare. Mostly it's those such as yourself who may not be world-class genetic outliers, but are pretty damn good at running and have done enough training and racing to be able to offer real world advice on what it takes to get from level A to level B - which is exactly what I'm looking for.
It might turn out that I was in fact born for the 10k and have been wasting my time at the longer distances. But I doubt it, somehow. Yes, you are better in your gender category than I am in mine. But I'm not sure how relevant that is. At the end of the day you were a marathon-trained 41.25 10k-er who now knows what it takes to get that down by 100 seconds. So am I - the first part at least. So would be interested to hear what your 6 days a week consisted of.
I think a sub 40 min 10K is very possible for you.....and I think you'll see it very shortly.
It could probably be done with 4 days training a week. Two quality days, a slow recovery run and a long slow run at the weekend.
Its very important that some work is done at race pace. Mile reps at 6:20-6:24 pace can't be underestimated.
But watch your weight on non training days. When I went sub 40 first time I weighed about 11 stone 5 pounds and was running about 25-30 miles per week (I'm 5'9). However sensible your training, it is very easy to pile on a couple of pounds on non training days.
I used to think the idea of easy mileage was a load of rubbish perpetuated by lazy individuals. I felt that the only true was to improve performance was to force the body to adapt to the demands placed on it through consistent hard training.
I was wrong!
Not only did I manage to give myself phases of achilles tendonitis, sesmoiditis and plantar fasciitis......my times also stagnated for nearly a full year.
Its important to read a few books about running, subscribe to a magazine such as.....Runners World or simply spend time learning from individuals on forums such as this.
The benefits of easy running include:
1) Improvements to the aerobic system. If you train at extended times for increasing mileages in lower rate heart rate zones, there is no two ways about it.....you endurance improves and your resting heart rate lowers.
2) An easy run helps you recover from a tough quality session. It helps keep the muscles supple, your weight nice and low and the blood in the right places for recovery.
3) Easy running helps you to work on form and cadence without the stresses of a tough workout.
4) A couple of days easy running helps also recharge you mentally (as well as physically) for the tough quality sessions.
5) As already indicated in my third paragraph, easy running can help with injury prevention.
If you are wanting to decimate your 5k and 10K times, why not try building up to a slow easy weekend run of 16 miles at 7:30-7:40 pace and see what it does to your times. I would also advise increasing the numbers of reps in your quality sessions. When I was at your level I was aiming for 12 x 75sec quarter mile reps with 90sec recoveries. I would also aim for 10 x 0.5 mile reps, but perhaps a little slower 2:50 pace?