Sprinting slower than normal and block breaking

Basically Block breaking/placing is slower the same with the sprint speed and you can really notice because the previous snapshot sprint and block placing was normal but now it is very noticeable

To reproduce all you need to do is
1.Sprint in 1.5.2 then in 13w21a you will see the diffrence
2.Place and break block in creative in 1.5.2 than in 13w21a