I was reminded the other day of a student I once had, named Louwtjie. I don't think he'd mind me using his name, as the story I want to tell will indicate one of the joys of teaching martial arts.

I was still a first dan instructor in my early twenties and taught in a hall that I rented from the university where I studied. I've had the school for a few years by that time (I started coaching before I had my black belt) and had many pass through my door.

One day, this fellow came in and said, "Hi, I'm Louwtjie. I'd like to train martial arts." The first things I noticed were his extraordinary thick spectacle lenses, and his one eye was slightly crossing over. He entered the training hall. Then he paused, deliberately, so that I could have a look at him. He was slightly below average height and average body size, and walked with some difficulty. He had some problems with balance and I just knew his motor skills were limited.

"Can you teach me?"

"Yes, sure, no problem." My lips said so, but my heart said: "Oh boy, oh boy, oh boy!"

So I lined him up right in the front row of the beginner's class and we started. The severity of the situation struck me then. This guy stuck out his fist in a punch – totally skew! His punches weren't straight; his arms seemingly didn't want to do any punching combinations. It looked like a one-two punch combination would entangle his arms! He had little balance and had a hard time not falling over with any kick higher than his shin. He even looked funny when he walked.

It was clear that Louwtjie's disabilities was making social life a strain, it prevented him from participating in any sport, and that was hard in his environment – he worked in the communications department of the police – a macho world.

The only thing that was stronger than his disabilities was his determination. He gave us all a lesson in willpower. He was my student for about a year. He trained hard, I can still see him standing in fighting stance, pushing his glasses back (which kept slipping down on the sweat dripping off his face), and overextending on his punches, losing his balance. But he kept on working hard. I didn't make it easier for him, either. In fact, if the class did 10 kicks, I'm made him do an extra 5 on each leg. If they did 20, he did 30 and so on. I just made sure that I told him after every class where he improved and where he needs to focus – just one or two things at a time. (Less is more in this case.) Then, I'd say "Well done." When we trained, he trained, when we sparred, he sparred and we hit him jut hard enough to make him realize it's real, but nobody took advantage of him (he wouldn't let them either). He prepared for his grading of the first belt and he passed, alongside some others in the group grading. Sometimes he'd turn up for the extra sessions I'd hold. He did the push-ups, he did the sit-ups, he punched the bag and he kicked in front of the mirror and did his balance exercises.

After a while, some of the students would comment: "Louwtjie is getting better!" and sure enough, there was a marked improvement in his athletic ability. After about a year or so, Louwtjie quit the training; I don't know the reason, but I saw him a month after he quit. I was on my bicycle making my way on campus, when I saw him. He was in front of me – also on a bicycle. He looked totally different from the man I knew a year earlier – sure he still had the thick glasses and his figure unmistakable, but from him gleamed a world of confidence. He stopped and dismounted and pushed his bike. I slowed down to keep watching. He walked normally – head up high. I stopped next to him. "Hi Louwtjie." He looked up and smiled "Hi Sensei, how are you?"

In my heart glowed the deepest respect, satisfaction and pride. "I'm well, thanks. What are you doing these days?" He said something about competing in sport – cycling, or swimming or something like that. I didn't hear properly, because through my mind went the thoughts of how this disabled guy with fear in his eyes of a year earlier, became a person with visible athletic ability, who does all kinds of sport presently. All it took was one coach who invited him in and gave him a chance – and didn't treat him like a cripple. But this coach also gave him clear structure on what he needed to work on, where he improved, and how and why and what's the next step. Yea, and he loved the fact that I pushed him harder.

A similar thing happened to my coach from another town. He had a student who had similar problems as Louwtjie – lack of balance, motor skills and coordination. The coach was a farmer and he instructed this student – his name was David – to come and train on the farm. David would be standing on one end of the field, while the coach was plowing the land, doing katas, or just stand there, punching and kicking. Every time the coach came past on the tractor to plow the next row, he'd shout new instructions as he rumbled on and David just kept on doing them. In 1996, this former disabled fighter, David Kies, became South African Middleweight professional kickboxing champion. All thanks to the coach, Henk Pelser, who was also the guy who coached me into the heavyweight title the following year.

I still don't know who make the biggest impact on whom – student or coach, but what I do know is that it is one of the most gratifying things that can happen to any coach. Don't show the cripple away from you school, you may just change his life – and he yours.