Biorhythms: The 1970s Fad That Won a Super Bowl, Killed Clark Gable, and Made America Gaga for Computers

It's called Biomate. I ran across an ad for it in a magazine from the 1970s and had no idea what I was looking at.

It turns out that this little device explains a person's biorhythms, which in turn explain everything—especially sports. Did you know that when the Minnesota Vikings' Jim Marshall made the historic blunder of running a fumble back to his own end zone, his biorhythms were on a "triple critical" day? Marshall had no idea either, but became a biorhythms convert once he found out. The theory works the other way, too. When Hall of Fame running back Walter Payton set a National Football League single-game rushing record that would stand for 23 years, he was peaking in emotional, physical, and intellectual cycles. Just look at his chart, which ran in newspapers across the country at the time:

When biorhythms are bad, as they were for National Basketball Association star Kareem Abdul-Jabbar one day that same year, things can go way wrong:

For a while in the 1970s, these charts were everywhere. Las Vegas bookmakers like Jimmy "the Greek" Snyder factored them into betting lines. Newspapers routinely interviewed experts to see how biorhythms would play out in big games and even big elections. The ability to draw up these charts for yourself was a major selling point for the earliest personal computers. The first team to exploit computerized scouting, the Dallas Cowboys, was also the club most heavily invested in biorhythms. All of which leads to a question: How did they get so big, and how could a tool with this much supposed explanatory power disappear so completely?

The rise and fall of biorhythms is a reminder not only that the 1970s were really weird but also that some of the easiest marks are sitting on the cutting edge.

Biorhythm theory owes its origin to a friend of Sigmund Freud named Wilhelm Fliess. A nose and throat doctor who thought sexual abnormalities could be corrected by applying cocaine to the "genital zones" of the nose, Fliess got the theory started after observing that the waxing and waning physical health of his patients seemed to occur in 23-day cycles. Subsequent studies by other researchers further developed the theory and also revealed 28-day emotional and 33-day intellectual cycles, rising and falling and repeating, a series of sine waves that begin at birth and continue reliably until death.

The really bad days are not at the trough of a cycle, but at the point at which a given cycle crosses zero, switching from positive to negative, or vice versa. That's a "critical" day. Two at once, like Kareem above, are "double-critical." "Triple criticals" happen about once a year. Biorhythm theorists advised being careful on any critical day; don't even leave the house if you're double or triple.

That's about all there is to it. It may not sound particularly convincing, but a few examples of biorhythms in action made believers out of many. Actor Clark Gable's heart attack happened on a critical day in 1960. Soon after, Swiss biorhythms expert George Thommen warned that Gable would soon be facing a double critical day, and that his health was in danger. Amazingly, he was right. Gable suffered a fatal heart attack on the very day predicted.

Such predictive uses of biorhythms were rare, but there were plenty of retrospective applications of the theory. Just look up a birth date, cycle forward to a key event, do the biorhythm math, and suddenly, the world looks a lot more orderly. Suddenly, every mishap or bone-headed decision has a logic to it.

Marilyn Monroe and Judy Garland fatally overdosed on critical days. Gerald Ford pardoned Richard Nixon on a critical day. JFK was assassinated on a critical day by a man, Lee Harvey Oswald, on a critical day, who the following day would be killed by Jack Ruby—also on a critical day. Ditto Lincoln and Booth. Ditto Chappaquiddick. Little Big Horn. Waterloo.

Buoyed by well-known examples, the theory became hard to dismiss. There were a handful of college professors throughout the country eager to support it, and it also benefited from sharing a name with a solid science—circadian cycles and all that. The fad-crazy nature of the decade helped as well. Thommen's initial biorhythms book from 1964 became a bestseller when reissued in 1973, and then the concept really exploded two years later with the publication of Bernard Gittelson's book Biorhythm: A Personal Science.

Offering copious anecdotes and biorhythm charts for the next four years, it became the go-to biorhythm book and Gittelson the go-to expert. He would be interviewed regularly about the theory in the coming years, while his book would go on to sell three million copies and be translated into twelve languages. People used the charts to test romantic compatibility and even to predict the gender of their child. If the mother's physical cycle was ascendant during conception, it would be a boy; if emotional, a girl. (To test this, I considered the birthdates of myself and my three brothers, turned back nine months, realized what I was calculating, and quickly turned my thoughts back to sports.)

The most popular section of the book concerned athletics, so Gittelson followed up in 1977 with Biorhythm Sports Forecasting. The book offers hundreds of examples across sixteen sports: Did you know Muhammad Ali had high physical biorhythms in Manila, while Joe Frazier's were low?

The back of the book lists a number of major athletes—and also celebrities like Cher and Hannah Arendt—paired with charts allowing readers to predict their performance. Only don't get the wrong idea: a blurb on the front cover warned in all caps, "Not intended for use by professional gamblers."

For further clarification, the back cover added, "This book is not designed to encourage gambling in any form. Its objective is to put an end to gambling losses."

Gamblers got the idea—and newspapers found it useful as well. Suddenly, sports pages were running headlines like "Biorhythms Favor Dallas," "Biorhythms: Dodgers Must Win in 5—or Lose in 7," and "Stabler's Biorhythms Portend Raider Win." The last story went on to note, "Bio-stat finds Ken Stabler peaking on physical cycle … and pluses in emotional and intellectual cycles. Franco Harris' bio-stat finds a minus physically, a plus emotionally and a minus intellectually. Terry Bradshaw just passed through a physically critical day Saturday before the game."

Amid much earnest effort to determine which was more important, the biorhythms of horses or their jockeys, one breeder in Maryland reported getting ten calls a week asking for her horses' birthdays. There was talk that Russia already was exploiting the athletic advantages offered by the new science.

A 1978 New York Times story said that managers for several Major League Baseball teams adjusted pitching rotations in accordance with biorhythms and that five NFL teams used them to scout opponents. Oddly enough, nobody was willing to go on record about using such a dubious tool—that is, except one of the most successful NFL teams of the era.

"We at the Cowboys were always looking for something to try that was new that would maybe enhance our chances at winning football games, and so anytime something like that came along, we became interested in it," says Gil Brandt, who served as vice-president of personnel for Dallas from the team's 1960 founding through its five Super Bowl appearances in the 1970s.

For a while, Brandt and the Cowboys took this stuff pretty seriously. In 1977, he told the New York Times, "I won't talk contract with a player on critical days … I don't know if what I'm doing is valid, but I think there's a lot of smart people who are into these things now. If United Airlines won't let their pilots fly on critical days, why should I bargain with the future of a player?"

(Amid probably exaggerated reports that Japan's railway system was guided by biorhythms charts, American airlines were rumored to be exploring them as well. United went on record about it, although it's unclear just what use they made of them.)

Brandt said he produced biorhythm charts for his own players but didn't tell them what they said. Opponents' charts he would bring right to Dallas coach Tom Landry. "We tried to find out who was going to have a bad day and who was going to have a good day," Brandt says now. "So if we thought that Joe Smith from our opposing team was going to have a bad day, we tried to take advantage of him, whether he was an offensive player or a defensive player."

The first year of experimentation with biorhythms culminated in a 27-10 Super Bowl victory over the Denver Broncos. Brandt said after the game that he had "spent at least 100 hours in four months" studying the charts, and so he surely saw it coming when Broncos' quarterback Craig Morton threw four picks amid an intellectual low. Brandt was a believer—"I'm just beginning to scratch the surface of the knowledge I want to gain on biorhythms," he said—but he sympathized with the Broncos' plight: "How do you bench a quarterback that helped you get to the Super Bowl just because his biorhythms are down that day?"

It's unlikely any team used biorhythms as extensively as the Cowboys, who did everything differently. They were the first team to integrate computers into their scouting, developing a continually updated, Madden NFL-like player-attribute rating system. "We were sort of light years ahead of anybody else," Brandt says. The advances brought an incredible stock of talent, two Super Bowl wins, and maybe an eventual Hall of Fame jacket for the 82-year-old Brandt.

The approach also put Brandt and the Cowboys in touch with a lot of flim-flam. "Everybody was trying to sell you something … and most of the time they were hare-brained schemes," Brandt says. "What made it so convincing for us to do things is because of the fact that we started the computer program in 1961 and it turned out to be very successful for us, and so with that lead in, we took a few chances."

Computers, everybody knew, were the future. So of course the Apple II and others came packaged with biorhythm programs. The opportunity to print out personalized charts was sometimes used as a way to attract customers to stores. For those not ready to make such a pricey commitment, malls, gas stations, and hotels added machines where people could get biorhythm print-outs for a quarter. Casio put out a calculator called the Biolator, which sold about a million units in 1976. For those on the go, Hewlett-Packard offered a watch version. It only cost $750.

A decade after introducing biorhythms to America with his prediction about Clark Gable, George Thommen told Time in 1978 that he was happy with all the attention they were getting but that he thought the "commercialization" of it was "a dirty trick." Bernard Gittelson had a lot to with that attention as well as the commercialization. He was selling a thousand personalized charts by mail per month in 1977. The last page of each of his books was an order form for about a dozen biorhythm products.

Gittelson was the best thing that ever happened to biorhythms, and biorhythms were the best thing that ever happened to him.

Who was he? The New York Times and many other outlets described him as a "behavioral scientist." It was said that Gittelson had "over thirty years experience" in the field, starting with a three-year stint at MIT's Research Center for Group Dynamics. In interviews, Gittelson said he had been a biorhythm skeptic at first, but he'd come around, convinced the cycles were reliable 80 percent of the time. It was a vibrant new theory that needed more testing, he insisted, but it was not at all like astrology.

There was more he didn't say. The son of Russian immigrants, Gittelson was born in New York in 1918. In 1939, he graduated from St. John's University. In 1944, he served as director of the New York Commission Against Discrimination, creating the first U.S. state law against discrimination in employment. Joining the American Jewish Congress the next year, he fought anti-Semitism as part of a group loosely affiliated with MIT. In 1948, he changed careers, joining with a friend to form the Roy Bernard public relations firm. It grew rapidly, opening offices in Britain, West Germany, and across the U.S.

Then, in 1961, something went wrong. A parking meter company was trying to secure a contract with the city of New York and was advised by Gittelson that a $50,000 bribe would do the trick. They gave it and got the contract, but word got out and a trial ensued. The meter people pleaded guilty; Gittelson said he had no involvement. Now he was up for perjury—27 counts. For three years, his lawyer delayed the trial on account of Gittelson's emotional instability, what his psychiatrist called "'a cyclothymic personality'—alternating between lively and depressed states." The prosecution said he was merely "unhappy." The court's psychologist agreed, and finally, in 1965, the trial began. A day in, Gittelson confessed everything. Yes, he'd acted as middleman for a bribe, but there was no bribe. He'd pocketed the money. In September of 1965, he was sentenced to a year in prison. He had already been forced to resign from the agency he had co-founded. A former colleague described him as "very bright with an awful lot of contempt for peo­ple."

In January of 1967, newly out of jail, Gittelson founded the Time Pattern Institute. For biorhythms? No, for that other thing, the one he would later insist that biorhythms weren't: astrology. By 1969, Gittelson was pulling in $2 million a year offering direct-order computerized print-outs of people's horoscopes. His venture was written up by the New York Times. His criminal past wasn't mentioned; he was merely "a 50-year-old former public relations man" who "decided in 1966 to seek a new career that would keep him near home." In the story, he was quite clear that the print-outs were just a business proposition. He'd studied the market and found a growth area. The next year, the Chicago Tribune ran virtually the same story, saying Gittelson "decided to give up his lucrative but demanding international public relations business. He wanted a new challenge with less travel."

Just like that, Gittelson had reinvented himself. In 1972, he started over again, getting into biorhythms. Not one of the dozens of stories on his biorhythms business mentioned his criminal record. Almost none mentioned that his true background was in PR, not "behavioral science." Not a single story mentioned that he'd recently been peddling biorhythms' downmarket cousin, astrology.

You can't blame all those journalists too much. Sure, some stories were pretty credulous about the theory—especially in Atlanta, which happened to be the headquarters of several biorhythms outfits like the one Brandt used with the Cowboys. Still, it wasn't nearly so easy to dig up people's pasts back then. Besides, Gittelson understood that modern innovations gave old-fashioned snake oil a new-fashioned patina: in addition to astrological and biorhythm printouts, he was also selling personalized diets, printed to order. He was working the new technology for all it was worth.

Of course, he was also selling people the tools to dismantle the whole thing.

The great thing about biorhythms? You didn't need an expert or an advanced degree to calculate them, just arithmetic or a calculator.

The terrible thing about biorhythms? Same.

"The reason it became so popular," says Terence Hines, a psychology professor at Pace University, is that "it was so easy to calculate somebody's biorhythms, and I think that was also the downfall. Once it became clear it was so easy to calculate, it was easy to show that it was bogus."

Hines first began poking holes in biorhythms in 1978, while he was a grad student. The next year, he was invited to be on a television program in Boston for a debate against Gittelson. Hines described him as "a personable guy," confident in his theory, confident that studies could prove it, and utterly unable to back his statements up.

Hines wrote a comprehensive takedown of biorhythm theory in 1998—he calls it the "most boring paper I've ever written or read"—which runs through 134 studies of the subject. A few of them turned up statistically significant findings. Very few. Most of the studies supporting biorhythms were seriously flawed, like the study of free throw shooting which gave 100 percent accuracy to everyone who went 0-for-0.

The problem for biorhythms, Hines says, was that the theory wasn't as malleable as pseudosciences like astrology, lacking the "multiple outs" needed to make it non-falsifiable. Not that Gittelson didn't try. He was eager to respond to counter-evidence that many boxers won fights and pitchers threw no-hitters on critical days. "Some performers are at their best in the clutch," he said.

Brandt and the Cowboys didn't drop biorhythms because of studies, but rather because of experience. "It was pretty good until we played Pittsburgh and they beat us in the Super Bowl," Brandt says of Dallas' 35-31 defeat in January 1979. "Bradshaw was supposed to have a bad day, and he must have forgot to read, because it didn't happen."

The Cowboys put the charts away. Everyone else began to do the same. There were fewer newspaper articles. The Chicago Tribune, which had been running daily charts since 1977, stopped just a few weeks after the Super Bowl. Yet there were some holdouts. Oddly, the Toronto Star, which had run a thorough debunking of biorhythms in 1977, hired Gittelson to offer daily biorhythm charts from 1981 to 1985. In 1986, Haim Saban sought to repurpose a Japanese show into a new kids' program called Bio-Man, "about five kids with identical biorhythms who defend the Earth." Only after dropping the biorhythms angle would it eventually reach the airwaves as the Mighty Morphin Power Rangers.

Gittelson moved on: he still produced biorhythms books through the 1990s, but he also expanded into the larger spectrum of pseudoscience, writing a book about "the world of psychic phenomena." In the mid-80s, he marketed an ESP reader called the Perceptron. He even convinced people to straight up trade him dollars at a loss. As he described his life when doing publicity for his 1982 book, How to Make Your Own Luck, "I've been working my ass off since I was 14. Lucky, hell." Gittelson died in 2010.

In something of a last gasp for biorhythms, an expert spoke with the Hartford Courant prior to the 1988 Super Bowl between Washington and Denver. The expert told the paper that Broncos quarterback John Elway would be peaking emotionally and intellectually, while his Washington counterpart, Doug Williams, would be a physical and emotional wreck. "If Washington has a second stringer, it may do better going to him," the expert advised. Williams was named MVP in a 42-10 win. Elway threw three picks.

Biorhythms are now dead. Their spirit, however, lives on—whenever sports analytics include "facial analysis," whenever the prefix "nano-" is applied to bubbles, whenever hologram bracelets interact with the electromagnetic spectrum to improve athletic performance. Like a sine wave, pseudoscientific scams may ebb, but they always return, buoyed by the next catalyst of credulity, the next technology of the moment.

Did you know you can chart biorhythms on your Apple Watch? It's called bioMate.