I am targeting a marathon in 6 months. I have limited time to train and have recently found it easier to drop the number of runs I do a week from 3 or 4 down to 2 - one long and one short/fast. The long is currently around 16km (~10m) and the short is around 10km (~6m). When doing 3 or 4 runs per week it seemed hard to increase the distances, but on 2 runs per week I have increased by about 1km per fortnight over the last 2 months.
My question is, will I be able to continue this cycle of two runs per week with gradual increasing distances over the next 6 months, or will I start hitting limits to what can be sustained on just 2 runs per week?
For info, I am 39 years old and am reasonably fit, having been running or cycling on & off for the last few years.