well im trying to lose weight so i have my elliptistrider machine for 45 minutes and up..i do jumping rope between 200 to 250 times but i end sore on my lower back at 3rd day;i do aero bic steps..well i need some tips or advice to get a complete routine exercise so i dont end sore again!!... im an adult female 5 f 7 i with 195 libras o_0..i have very low metabolism with severe constipation..i appreciatte your advice thanks!!!