Originally Posted by
Maelochs
Add the weight of the bike to the weight of your body, figure what percentage of that is ten pounds, and that is the percentage lless energy it will take to move the lower mass. Pretty minuscule. if you drop ten pounds of fat ... great. If you drop 15 pounds of fat and ad five in muscle to your legs, better .... but if you ride a lot of high-intensity intervals and hill repeats ... you will actually ride faster and climb hills more easily. Weight loss is never a bad thing .... but it is proportional. Unless you are cutting off your arms ..... not a Huge difference.
Add increased fitness, and ..... well, see what yo see and do what you like .... whatever works for you.
For what it's worth, the conditions that lead to building muscle tissue, and to burning fat, are almost opposite. Losing fat is easy, you just have to burn more calories than you eat. Building muscle is hard, you have to do progressive overload while eating enough carbohydrates and protein, and you almost need to be eating more calories than you burn. It costs a lot of energy to build muscle, and to maintain it, so the body doesn't like doing that in lean times. Most people will be better served taking the two goals you mentioned separately, one then the other.