The first thing I noticed was how flat footed your landing right from the drive phase it seems to the finish.
How much attention do you pay to strengthening/elasticating the achilles tendon/calves/shins/ankle complex away from sprinting alone?.
Your losing a lot of power there, hence time. Some circles say those provide 20-25% of the power needed for an explosive start but get even more important as you climb to maxv. Your going to run a hell of a lot faster decreasing ground contact times, yours being very long (flat footed). Checkout the frame at 0:19 at ground contact for example. It seems the whole race was run that way?.
Away from there, obviously your hip extension strength is good.
In the gym, I would start paying more attention to increasing/strengthening the ‘power’ in the core/hip flexion region, develop the tendons of the deltoid region (long/short head of biceps brachii) & obviously making the lower limbs stiffer/more elasticated (achilles tendon/calves/shins/ankle).
I have always concentrated on dorsiflexion but I had non in that race. Last year I was having tight calf issues. It may be the cause. What excercises would you suggest for me to increase core and hip flexion. Thanks