Sub-four At 40?

•The historic 3:49.4—the first mile under 3:50-came on Aug. 12, 1975, in Göteborg, Sweden. It was only Walker's 11th sub-four race, and the photo of him crossing the finish line is one of the most famous in track and field. In the photo Walker, his mouth agape and his head thrown back in agony, looks as though he had run smack into an invisible force field. Seven years passed before he lowered his best again, running 3:49.08 when he was 30 in a race won by Scott in Oslo. He is still history's eighth-fastest miler.

•Twenty-one of the miles were run indoors; two were on grass tracks outdoors.

•The oddest of the lot, in Walker's opinion, was the mile he lost to Eamonn Coghlan in Tullylease, Ireland, in 1981. "The meet was organized by a priest," recalls Walker. "He redirected traffic so that every road in the area led to the track. Then he charged people a pound whether they wanted to come or not. Only in Ireland."

•He ran his 100th, a 3:54.57, on Feb. 17, 1985, at Mount Smart Stadium. The circumstances surrounding that race say a great deal about Walker's hunger to reach milestones. Scott, another prodigious miler with 96 sub-fours to his credit at the time, had proposed that, to heighten the drama and generate publicity for the sport, Walker wait until Scott reached 99 too and that they go for their 100th in the same race. Though he regards Scott with deep respect and affection, Walker refused.

"All that counts is who's first," Walker says, without a hint of apology. "That's why I couldn't share Steve's sentiments, standing around waiting for him to come along. No one cares who's second."

Scott, it must be noted, has since passed Walker, with 141.

As amazing as it is that a 40-year-old might run under four minutes, it is doubly amazing that it is Walker who has lasted this long. At the Montreal Olympics in '76, Graeme Campbell, New Zealand's team doctor, took Jelley aside. "He told me that John's Achilles tendon was so fragile that he couldn't see it lasting another season," says Jelley.

Nor was the Achilles Walker's only injury. Shortly before the Games, he had developed a mysterious ailment in his right leg. Exactly 30 minutes into a run, no matter at what pace he was going, the leg would go numb, and he would have to stop. "It was like an alarm had gone off," he says. "It felt as if a giant hand had grabbed it and was twisting."

Jelley, ever resourceful, worked around the injury. "What he'd do," says Walker, "was take me up to the Waitakere Ranges, the mountains where Snell used to run. There's a hill there that's two and a half miles long and a real gut buster. I used to flog myself right from the bottom to the top of it as fast as I possibly could. That took 15 minutes. Then he'd put me in the car and run me down and I'd do it again. That was the hardest training you could do. You wouldn't normally do that training. You just wouldn't attempt it." In 1977, with this as the staple of his training, Walker ran 1,500 meters in 3:32.7, fastest in the world that year.

Walker visited 30 doctors in 2½ years before the problem was finally diagnosed as "muscle entrapment," a condition in which the calf muscle expands, cutting off the flow of blood through the artery. "They cut me from one end [of my calf] to the other," says Walker. It took 160 stitches to sew him back up. In the summer of 1979, when Walker came back, he had changed tremendously.