This has happened to me, twice so far. As background, I’m 5’9", and weigh about 170 lbs. I am male. And although it is of course not apparent from looking at me, I’ve practiced martial arts, of various forms, for many many years.
Neither of my attackers were particularly muscular- street assailants often seem to rely on surprise rather than true intimidation. One of my assailants was quite simply grossly obese. Knowing that a body blow to him would do little good, and that he probably had week knees already as the result of his absurd weight, I left him in the alley with a dislocated knee. The second assailant was a youth, smaller than myself, who brandished a knife at me. I used a technique similar to that described above by bippy to deprive him of that knife and use of that hand, and introduce him forcefully to the ground.
In either case, after the action, I quickly assesed the surroundings, and backed away. After reaching a safe location, I called the police. Neither attacker was ever apprehended.
BUT- each confronation is unique. There is never a set way to deal with any incident. The key to succesful self defense is awareness. It begins with avoiding dangerous situations like this, and continues with the rapid assesment of the situation and the on-the spot planning to end the situation as soon as possible.
For this case, with the person hypothetically bigger/stronger than me, I’d consider a range of techniques, coming down to using his grab/punch momentum to break an arm or wrist, and following with a strike to the classis hurt-em-quick points- knees, shins, groin, solar plexii, neck/larynx, or eyes. Knee kicks are taught as gospel in so many one-day self defense courses, they’re becoming expected, leading to the risk of a block. I may avoid them in the future if this ever happens again. The goal would of course be to end the confrontation in one strike, rendering the attacker unable to continue or pursue. Then back away, escaping asap to a safe location. If one strike cannot put him out well enough to let me escape, then things get nasty and I may have to do permanent harm.
The most important thing, though- THINK. As Mr Adams teaches us, DON’T PANIC. 90% of the time, alleyway assailants are after a quick buck, and putting up any fight at all will send them running (or crawling or limping) on to the next victim. And don’t use any more force than neccesary- thanks to our justice system, this turns you into the criminal.