Bro Manny is no PBF in terms of skill but he is definitely above average in that department. Regarding his physicality his stamina and explosiveness has always been there. It's only after the Marquez rematch that PAC utilized more his lateral movement and right hand has improved greatly. In order to develop speed increase in muscle power is required or increase in your fast twitch muscle fiber which in most cases is being accompanied by hypertrophy which in Manny's case does not show. As stated by Adam in the previous post there are some steroid/or HGH that improves your cardiac muscle to improve stamina, Bro Manny always had great stamina.
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