"Physical training consisting of alternating
periods of high- and low-intensity activity."
Intervals are integral to improving your speed and power endurance for events such as the 10k where you need to be able to maintain a pace just at the very threshold of it starting to really hurt. By building up your training with intervals, you will increase your body's ability to deal with these high-output activities.
And they aren't just for road and track runners, building intervals into your training will improve your trail and fell running too!
The key to good intervals is really trying to recover inbetween each one. That means really slowing down. Walking even. Don't worry that this will bring down your overall pace for that run.
Find yourself a stretch of road, track or field that you can happily run around on. It is also worth having a watch with lap facility or GPS so that you can measure each interval and your pace. You can also measure sections of road on this website.
A heart rate monitor will let you get really nerdy with the stats but you should be able to judge your effort level without one.
There are several online pace calculators. Decide what time you want to run your event in and then work out what pace you will need to run at to acheive this; for example, if you want to run a 40min 10k your pace should be 6min 24sec a mile.
Don't worry if you fail to achieve your hoped for race pace (if that is what you're hoping to do in the interval), it is almost impossible to replicate race pace on your own. Instead, aim for consistent splits (i.e. a steady pace throughout each interval and across your intervals). Your pace may drop off through the session, don't worry, just try and keep going. Its better to persevere than sack it off.
This is an example of a interval programme for a 10k.
Give yourself a 2 month (8 week) training period before your 10k event. This will allow you to build up to your hoped for race pace and that PB.
This is a weekly breakdown of that training period. Try to do these sessions once or twice a week, around your normal running, still running some longer, slower runs and a short tempo run (a fast pace that you can maintain) too. These will actually aid your recovery from these sessions.
*Note - You will always manage to run faster in a race, that's what makes them magic!
Week 1 & 2: This is your benchmark session from which you will improve so don't be worried if it feels hard, it is meant to be! After a 5min jog warm up, find a mile of road, track, path or field that you are happy running on. Run 1 mile as close to (but probably quite a bit below) your aimed for 10k pace. don't be tempted to go faster, this is your race pace, not sprint. Once you have run a mile, jog for 3-5mins and catch your breath. Really slow down for this, walk if necessary. Then run a mile again, at race pace. Do 4 of these. You have now run 6.5km at close to race pace. Warm down with another slow 5min jog.
Week 3 & 4: After the usual warm up, run 2mi as close as you can to race pace. Recover with a 5min jog. Now run 2x 1mi intervals aiming once again for race pace, with 3-5min jog recover, as per the last couple of weeks. You have now run another 6.5km close to your race pace. Warm down with another slow 5min jog.
Week 5 & 6: After the usual warm up, run 2 x 2mi as close as you can to your race pace with the usual 5min jog recovery inbetween and a 5min warm down jog. If you struggling to get even close to your hoped for pace during this session, you may need to lower your aimed for time by a few seconds.
Week 7: This is a hard session and should be approached when feeling fresh and ready. After the usual warm up, run 3 x 2mi intervals (at near-race pace) with the usual 5min jog in between.
Week 8: No intervals this week. Instead try to relax; if you do run, make it a gentle jog and certainly no hard or long sessions in the days prior to the race. Eat well, drink plenty of water, keep of the Cab Sav and get plenty of sleep.
Let us know how you get on!