I do have a weighted vest, I introduced it on runs very gradually, 1lb of weight, as i lost weight i put half of that lost weight into the vest.... i.e. I lost 20lb of weight, but put 10lb back in the vest.
Now I didn't notice it going in there at the time, and when i took it off oh my my running felt super quick...
Mind you, will I do it again? (i only did that for about 2 months), probably not, it did make me slow down mind you as I couldnt made the pace, but being concerned over my knees etc I have opted out...
For hill repeats I might, and i say might wear a mild amount of weight to add that little extra, but shall see...
Would i recommened it to anyone, probably not, its something I am aware of the possible dangers and it just for me adds a bit of variety. from the articles ive read about using them, they only suggest using them on shorter runs, upto 3-4miles at most.
One thing i did notice after using one mind you, was my push off was sharper, but then its just like running uphill all the time, so its not going to do wonders for your speed, just increase your strenght (yes i know that sounds a bit controdictory :S)
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