vespario wrote:Tend to ride about 100 + miles a week in winter. One 70 club run plus one or two shorter rides in the week.
During school holidays this goes up to about 150 a week to 170 depending on weather.
Tend to average around 17mph on most rides or so my garmin tells me.
First of all ride more frequently, 3 rides a week will not really help build fitness, you would have lost virtually all of the fitness in the 4 days you are not riding. If you can try to ride 3 to 4 times during the week, have a rest day before the 70 miler, you will eventually get fitter.
If you can only do an hour or so on each ride during the week, up the intensity, no point doing you 70 mile effort/pace for less than 3 hour IMO. 60 mins at high tempo is a good start, or if you can manage it at sweetspot, but if you are not that fit that might prove to tiring if trying to ride more often as well.
As above, seeing you can do 2 hours at a good pace, strength is a non issue, cardio fitness is the issue.