The goal of any training programme is progression, which just means doing a bit more each week so that your body becomes accustomed to the extra demands you are placing on it. Don't be tempted to overdo it by increasing your weekly or long run mileage too quickly (10% per week is a good rule of thumb), failure to adhere to this rule is the most common route to a running injury. On the other hand if you don't stretch yourself a little each week you won't progress, so it's important to find the right balance. Varying your weekly runs is a good idea and helps to avoid boredom. Besides a weekly long run add a shorter faster run and two or three easy runs of varying distances. How long is long and how short is short will depend on your current fitness level and running experience and will change as you progress.

With 13 weeks to go to London you should now be well into your stride. If you're lucky enough to have a London Marathon place and haven't started training yet then don't delay a moment longer. For those just seeking to complete the marathon without any particular target, by the end of January you should be aiming to jog or run/walk 10 miles or to train for two hours and should be training at least three and ideally four times per week.

For those chasing a particular finish time then you should calculate what that means in terms of your required average marathon pace (eg, to finish inside four hours you need to run at 9 mins/mile) and should structure your weekly runs so that some are faster, your long run is slower and at least some sections of your other runs are at marathon pace. You should try to train five time a week taking your rest days after your most intensive sessions.