Improving 10k with regular training

[MMS]

Hi Coach,

Yesterday I had my 10k race and finished in 47:58. Not exactly what I had in mind, but it was a reasonable result, considering it was a warm day.
I could keep the pace I wanted only for the first 3km, after it I got slower, no matter how hard I tried to push. Between the 5th and 6th km we crossed a bridge, so there´s an uphill here. We double back and between the 6th and 7th we crossed on the other side of this bridge. I felt some dizziness after these two uphill parts, but it was gone right after and I kept going. I had some energy left for a small sprint near the finish line.

Here´s the splits:

Mar 27th - 10k race

Km|Time|AHR
01|04:25|172
02|04:30|183
03|04:35|182
04|04:50|187
05|04:45|187
06|05:02|188
07|05:05|190
08|05:06|191
09|04:55|190
10|04:45|192
Tot|47:58|186

Only after the race I checked my pulse and saw that from the 4th km I was near my limit. My watch even registered 9min38s of pulse above 190 (as it was my max HR).

Now, next race is the half marathon on April 10th. I´ll start a new cycle tomorrow.

Have a nice week!

MMS

ps: some friends also ran yesterday, they already had a sub45 but didn´t make it. All of them, 3 friends, finished between 45 and 46 minutes.