Some Figures

Runners often get injured during the pre-season period: ie the bit after the cross country season and before the real summer racing season. There is a temptation to go too fast too soon. The next problem is that the athlete wants to do some training which is not running. Bikes and swimming are useful alternatives but how much? There are two wee equations that are often used to gauge how much.
One Mile of Swimming = Four Miles of Running and
One Mile of Running = Four Miles of Cycling.
So instead of running for ten miles you can swim for two and a half miles, or cycle for forty.

Others want to go for a longer race than usual - maybe move up to the half marathon or even the full marathon. The question then is how much training do I need to do?
If all you want to do is run and finish a race then there are two rules of thumb. The first is that you can race three times your average daily mileage. ie to do a marathon you need to average eight miles a day, to do a half marathon you need to average three and a half miles a day for the seven day week. Alternatively it is possible to race one and a half times your longest run of the week. So for a marathon you need an eighteen miler once a week in the lead up and for the half marathon you need a nine miler once a week. It should be well noted that these are for people aiming to run the distance; if you want a high level performance, you need to do more extensive training.

On the track, we can all work out the number, time and distance of reps but the real question is how fast do we do the recovery jog? Too often the jog is fast at the start of a session and gets progressively slower as the session develops. The usual pace of the recovery jog is 90 seconds for 200 speed and pro rata for other distances. Another wee thing - if the session is a speed endurance session then keep the recoveries very tight to the 90:200, if it is a strength endurance session then the speed must be constant and the recoveries can drift a bit - but not too much!