I'd recommend 'Hajime no Ippo'. While not focused solely on muscle girls, there are some notable female characters with considerable strength and determination. The manga is known for its detailed boxing matches and character development.
One popular manga with a muscle girl is 'Sakura Gari'. It has an interesting storyline and well-defined characters.
Chapter 479, ", Apocalypse-level Technology", is the clearest early answer because Dreadnought Mech finally turns buildup into a real advancement. It opens with [Dreadnought Mech] and [Strike Cruiser] are both part of Star Warrior... and closes on A considerable part of particularly dangerous battlefields was.... The key payoff is that it turns Dreadnought Mech's growth into a concrete upgrade step and sets up the next payoff in the power growth storyline linked to Battle Group.
Chapter 423, ", My Hero", is the clearest early answer because it turns Gu Hang's situation into a concrete plot event. It opens with Yelisia felt somewhat nervous, for she didn't know exactly what Gu... and closes on One rocked back and forth on a reclining chair, the other sat beside,.... The key payoff is that the chapter closes with The Dragonhawk and Rage Bear Star Realm Army Corps would remain on Steel Wing Star as defense forces.
Chapter 436, "Seven Horses Come to Join", is the clearest early answer because it turns Purple Horse's situation into a concrete plot event. The chapter gives readers a real answer by opening on Had it been just that, it might have ended there. and ending on All these factors were incessantly battering the psychological....
Chapter 44, "Actively Hunting I", is the clearest early answer because it turns Actively Hunting's situation into a concrete plot event. The chapter turns that into something concrete by moving from «You have slain a Grade Five mana beast! to Damien sat atop his wolf, his eyes scanning the area for any anomaly.. What makes it stick is that the chapter closes with It was then something rang in his mind. These were demons. Tree demons.
Chapter 482, ", you made the right choice", is the clearest early answer because it turns Imperial Tax's situation into a concrete plot event. The chapter turns that into something concrete by moving from She didn't ask why they had to go to these lengths. to A year ago, Gu Hang had contacted Galaraldo to ask about the....
Chapter 486, ", Only You, My Friend", is the clearest early answer because it turns Gu Hang's situation into a concrete plot event. A useful checkpoint is the way the scene starts with Riding inside, deep beneath the Imperial Palace, the track twisted... and follows through with I'll try to reduce the current debt as much as possible!. By the close, I know we all have our connections, but who would complain about..., and the chapter closes with I will definitely add an update tomorrow!
Chapter 484, ", Confronting the Trial", is the clearest early answer because it turns Fury Flame Battle's situation into a concrete plot event. It opens with Even towards the end, when the form of battle became deadlocked, the... and closes on Zuo Zhaofeng, on behalf of the Imperial Space Domain Government,.... The key payoff is that the danger stops being abstract and the conflict around Fury Flame Battle becomes immediate, forcing the surrounding cast to react under pressure.
Chapter 54, "First Real Combat III", is the clearest early answer because it turns Damien's situation into a concrete plot event. The chapter turns that into something concrete by moving from Ouch!" Damien was forced to wake up after falling off the tree he'd... to Almost feels like an unlimited weapon in my opinion." Damien readied.... What makes it stick is that the chapter closes with Brandishing his sword, he moved.
Chapter 141, "Demon Infestation Mission II", is the clearest early answer because it turns Damien's situation into a concrete plot event. Early on, Damien moved into the shadowy recess of an alley, checking for any.... By the end, A wave of decay and dread radiated from the hole, making Damien's....
Chapter 502, ", Financial Allocation", is the clearest early answer because it turns Gu Hang's situation into a concrete plot event. The chapter turns that into something concrete by moving from Anyway, the Alliance now controls the Star Domain Government, which... to Gu Hang currently has quite a few Grace Points at his disposal!.