Set my PR in 5K and 10K

I did 10K on the track yesterday in a bid to set my PR (Personal Record) so that I have something to target and aspire to go past. I was quite well prepped though the sun did roast me quite a bit, which was okay but I am sure I could have done better without it and without the wind blowing against my chest (this business of "wind-assisted" and "wind resistance" makes sense when you run in an open field and the wind is blowing against you directly).
I started at around 5.20pm. There were around a dozen runners. One boy was quite impressive, his pace was faster than mine and later after I was through with my laps, he inspired me to do some frog jumps and some pylometric excercises, which I clearly need in order to have stronger legs and to increase my bounding and leaping for longer strides.
Anyways, I did the first 6 laps in under 2 mins each - between 1:33 and 1:50 and finished the 12.5 laps (5K) in 24.15mins. Then a stitch hit me after the 6th Kilometer, slowing me down considerably. In the end, I did 10K (25laps) in 52.50mins. Recall that I just did a tough half marathon 6 days ago, so this is not so bad I guess.
One of the things that keeps me motivated about my running is competing against myself and bettering my times over time. Some four weeks ago, my best time for 5K was 27mins. Now I am at 24.15mins I intend to push it to 23 or 22 in 4 weeks and push my 10K time to sub 50 mins in the same period (48mins would be excellent). I think its possible and achievable, particularly if I shed off the remaining 5Kgs, add pylometrics and long distance in my training. My compartment muscles are definitely stronger because my shins are comfortable. In the past, my body would swiftly punish me with a sharp pain in my shins every time I tried doing fast runs.
Oh, by the way after running on the track yesterday after close to 8 months on the tarmac, the tracks are definitely easy on the body. I will be going for some 58 laps on Sunday. Though its not very good for teamwork, I would like to ensure I cover the first 53 laps in under 2 hours. I have some colleagues who haven't run long distances, who will be coming out to test their endurance and who may need someone to pace with and encourage them. Let’s see how it works out. There are three guys who may be willing to join me in the sub 2hour quest, a quest we can repeat 4 times before the marathon on 26th October.
Today I am resting. I had a 7Km walk to push my MBR up a little. Tomorrow, I will do day 2 of week 5 of the 100 pushups challenge.
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