The other day MarkyD responded to a post by LisaGuy-Cowes, healthunlocked.com/couchto5... about increasing distance after injury. He advocated the 10% rule, stating “Add no more than 10% distance each week, so 3x 5km runs mean that you are running 15km. Next week don't run more than 16.5 km in total. “
I responded that my understanding of the rule was “if you did 10k long run one week then you can increase to 11 the following, assuming that any other runs of the week are of lesser distance or duration. “
Rignold agreed with MarkyD that it was based on the weekly volume rather than the length of your long run.
Now,I have been aware of this rule since graduating, and in fact dismissed a 10k training plan because the first run on the scheme was 6k, when I had never run more than 5k up to then. The knowledge was probably passed to me by some wise graduate on this very forum and I have been repeating my interpretation of that rule over the years. Anyway, this query made me do some research about the 10% rule and these are my findings.
Firstly, the rule states that you should never increase your weekly mileage by more than 10 percent over the previous week. runnersworld.com/running-ti... Nowhere can I find my version of this, that it is based on the distance of your long run, and duration does not seem to get mentioned at all. The differences in interpretation can be significant.
Take my base running as 2x5k and 1x10k per week, total 20k. With my rule that 10k run could be increased to 11k in the first week, 12.1k in the second week, 13.3k in week 3, etc.
With the weekly distance version, my long run could be 12k in week1, 14.2k in week 2 and 16.6k in week3.
This article strengthrunning.com/2010/06... has some useful tips for new runners but also some ideas that need to be exercised with caution. The writer suggests that you could decrease one of your weekly runs and add that mileage to your long run. If taken to extremes that could mean from my base I could drop my 2x5k runs add on the 10% and go for a 22k run, a half marathon, for god's sake, with no intermediate training. Certainly not a wise approach for new runners.
However I did think “As a newbie, don’t increase your mileage every week. Keep it the same for 3-4 weeks at a time to allow your body to adjust.” from the same article was well worth bearing in mind, as it is often immediately post graduation from C25k that impatient new runners overdo it.
Probably the most interesting article I found was runnersconnect.net/coach-co... which discusses research which has failed to establish any scientific proof that the 10% rule actually works at all in keeping injury risk any lower than increasing distance by a greater amount. Also covered are other factors to take into consideration when upping the miles. For me, general fitness levels and age have a major bearing, especially on recovery. Despite being fitter than ever in my life, I don't bounce back from injury as quickly as I used to.
Let's face it 10% is an arbitrary figure. It just happens to make the calculation easier than 9.87% or even 15%. So as a guide it is well worth keeping in mind, and I am now a bit clearer about its application. To sum up, I apologise to anyone who took my advice, cursing as it seemed to take an age to get their mileage up. At least I didn't push you too hard and I am sure you didn't get injured. The other lesson to learn is that there is nothing to beat your own research.
Keep running, keep smiling.
The running pedant.