We use bench shirts (denim, double denim, poly, etc) to get more out of our lifts... In competition meets We must have our shoulders on the bench, and we must have our butts on the bench also we must also have our toes on the floor (some federations require that your feet be completely flat on the floor)..these are the rules, if your but, feet or shoulders ever leave the bench during a lift you are disqualified.. Now, basic knowledge tells us that when we are moving heavier weight the best way to do this succesfuly is to move it the shortest distance possible... the longer the distance the longer we have to maintain the weight, and the longer the distance the more effort it takes to move the weight..and thus increases our chances of NOT making the lift..so in this case..shorter is better...
This is where the Big arch comes into play... We try to get as big an arch as possible, Like sticking our stomachs up as high as we can.. We actualy bench off of our stomach's not our chests... And this is where shirts come into play.. We use our triceps more in our benching than we do our pecs... So when the weight is at the bottom (on our stomachs) we don't reallly have a lot of recruitment from our pecs (we still use them, just not as much) so the shirts help get the weight off of our stomachs...basicaly the shirts are so tight that they help reduce the weight a bit at the bottom....so by taking off that little bit of weight (the tighter and denser the shirt, the more weight it helps take off at the bottom) It allows us to be More explosive, and get the weight moving a little faster than we would be able to normaly (the extra momentum we get from this speed burst helps us move heavier weights... The shirt helps in the lower 1/4 movement of the lift, other than that, it's mostly just raw tricep strength...
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