The TRP concept of "pushing through LMR" is based on assuming the woman wants to have sex, but is unwilling to say so. Thus, should she decline sex, but throw up certain signs perceived as IOIs (making out in bed, wearing certain clothing, a "soft no"), the TRPer will continue anyway, despite objections.

This tactic operates under the assumption that if she truly doesn't want to have sex, she will become more forceful in her declination. Every time. Without fail.

But people are more complicated than that, and there are more factors in play.

Maybe she's scared to resist. After all, if you've been lifting; you're bigger than her. The implication is there: that you might hurt her if she fights harder. After all, most people will cease initiating when their partner tell them that tonight's not a good night. Continuing anyway puts you into an unknown category, and that could cause them to think of you as dangerous.

Maybe she's too tired to resist "properly." She might be too awkward, or shy, to make her needs clear. There's any number of reasons she might not be giving that "hard no."

You never know, though. Maybe she does want to have sex: but you can't know for sure. There's not enough evidence to be sure. Maybe she doesn't want it.

And if she doesn't: you've committed a rape.

Verbal, enthusiastic consent. This is the only way to know for sure that sex is what's on her mind. This is the right way to initiate sex. It's what's best for both parties.