Muscle　strength　training　is　to　reduce　muscle　atrophy　and　increase　muscle　strength.　For　ankle　joint,　we　developed　six　robot-assisted　muscle　strength　training　modes,　namely,　continuous　passive　motion　(CPM),　isotonic,　isometric,　isokinetic,　centripetal　and　centrifugal　exercise.　The　paper　aims　to　evaluate　the　performance　of　different　robot-assisted　training　modes　based　on　angle/torque　and　surface　electromyography　(sEMG)　characteristics.　The　sEMG　characteristics　were　used　to　extract　the　features　of　the　degree　of　muscle　activation,　while　the　angle/torque　information　were　used　to　calculate　the　endurance　ratio　(ER),　peak　torque　(PT)　and　torque　acceleration　energy　(TAE).　Experimental　results　showed　that　the　level　of　the　degree　of　muscle　activation,　PT　and　TAE　in　CPM　were　low,　and　ER　was　about　1.　For　isotonic　exercise,　isometric　exercise　and　isokinetic　exercise,　most　of　the　evaluation　indexes　including　the　degree　of　muscle　activation,　PT　and　TAE　increased　significantly　compared　with　CPM　(For　isotonic　exercise,　ER　is　1.09　±　0.25,　$r$　(LG)　is　0.0538　±　0.0171,　$r$　(MG)　is　0.0430　±　0.0116,　$r$　(SO)　is　0.0642　±　0.0178;　For　isometric　exercise,　PT　is　0.72　±　0.16,　TAE　is　2.15　±　0.51,　$r$　(TA)　is　0.0532　±　0.0256;　For　isokinetic　exercise,　PT　is　0.72　±　0.16,　TAE　is　1.99　±　0.82).　The　results　reveal　the　different　performances　among　different　modes,　thus　lay　a　foundation　for　exploring　subject-specific　adaptive　ankle　muscle　strength　training　strategies.　©　2018　IEEE.