You need to up your running. I can't stress enough how much you will kick yourself when you realise that your cardiovascular isnt good enough when you do you PRMC.
Also try some interval training. This could include sprinting from lamp-post to lamp-post to increase you anaerobic fitness and the power in your legs.
With that bike session you could do 20 minutes of:
20 seconds 30% maxium effort
20 seconds 100% maximum effort
20 seconds 30% maxium effort
20 seconds 100% maximum effort
.....and so on
Interval training is very good for capillarisation, strengthening the heart muscles and increasing oxygen uptake. Find a hill too for endurance/strength.
Just found this, best of both worlds - sprinting and endurance :
"South African coach Abrie de Swardt has come up with some excellent tips for hill training in a recent issue of The Coach. Hill training, as you may be aware, offers the following benefits:
-helps develop power and muscle elasticity;
-improves stride frequency and length;
-develops co-ordination, encouraging the proper use of arms during the driving phase and feet in the support phase;
-develops control and stabilisation as well as improved speed (downhill running);
-promotes strength endurance (very important for us lot);
-develops maximum speed and strength (short uphill runs).
Abrie de Swardt is a big fan of hill training for endurance athletes and believes it can make the difference between winning and losing. Here are a number of ways to complete hill sessions that will help elevate your performance:
Short hills – 5-10 seconds to improve the phosphocreatine system of anaerobic energy production (speed strength) or 15-30 seconds to improve the lactic (glycolytic) power system;
Whistle hills – controlled by the coach with a whistle, eg sets of 10s, 15s, 20s, 25s flat-out sprints, with an easy recovery jog of one minute between each and 3-5 minutes between sets;
Short hills of 30-80m to develop speed strength;
Longer hills of 150-200m for strength endurance;
Hills of 400-1,000m and hilly circuits over several kilometres for ultra-distance runners;
Downhill sprints over 50-80m for increased leg speed;
Hill bounding or hops and skipping over 30-80m"
http://www.pponline.co.uk/encyc/endurance-training.html
you don't want to over do it from the start trust me i would know.
!! Cheers for your comment mate! I used to run so much and i seemed to get myself to a base level of fitness but after over a year of running i seemed to have been hitting a barrier of which i cant seem to break through and increase my speed. But ill keep at it, or die trying!!! 