The Commonwealth Games were moved by only 24 hours and are scheduled to begin on July 28 in Birmingham in England, but the sporting schedule now also includes the World Games a few weeks earlier in Birmingham in Alabama.

They were originally to have taken place in 2021 and expect to attract 3,600 competitors from more than 100 countries in an event organisers insist will "showcase a new generation of global sports".

It was 40 years ago that the first World Games were held in Santa Clara, California. Of the original programme, badminton, baseball and softball, taekwondo, trampolining and karate all later took their places on the Olympic programme.

Yet the 1981 World Games began against a backdrop of unease.

United States Olympic Committee President Philip Krumm branded them "a splinter group" and "harmful". His comments reflected the concerns of other members of the "Olympic Family" that they might also have an impact on television income for existing events.

The World Games had been conceived as "a forum for those without Olympic recognition".

In October 1975, the what was then he General Assembly of International Sports Federations (GAISF) met in Montreal.

Led by Thomi Keller from Switzerland, the influential head of World Rowing, the gathering included Olympic sports but also non-Olympic sports.

In the days before Agenda 2020, the possibility of Olympic inclusion for many sports seemed remote.

The World Games idea was announced by GAISF secretary Oscar State, a veteran official in weightlifting.

There would be no more than eight sports and professionals would be eligible, it was decided. Softball, tennis, golf, waterskiing and tug of war were lined up for inclusion.

"There are a couple of other possibilities," State had told reporters.

Mexico City had been the Olympic hosts in 1968 and had expressed interest in staging the World Games. This was partly as a means of using the facilities constructed for the Olympics. The Philippines, then ruled by President Ferdinand Marcos, was also said to be keen.

Although 1977 had been suggested for the first event, the idea did not take concrete form until the end of the decade.

State had been succeeded as GAISF secretary by International Judo Federation President Charles Palmer, a supporter of the World Games. Palmer had been a first-hand witness to judo’s own struggle for Olympic inclusion over the previous decade.

He insisted that the World Games proposal was "certainly not in competition with the Olympics" but suggested it "really would be a consolation for those sports which cannot get into the Olympics".

By then, World Taekwondo Federation President Kim Un-yong had also become an important GAISF personality. He proved crucial in providing impetus for the World Games and was also a leading figure in Seoul’s 1988 Olympics. He was understandably keen for taekwondo to gain Olympic acceptance, an ambition ultimately fulfilled.

In October 1979, after a GAISF meeting in Monte Carlo, it was announced that the first World Games were to be held in Santa Clara.

In May 1980, the non-Olympic International Federations gathered in Seoul and a formal International World Games Association was constituted with representation from 12 sports.

It was a moment which largely passed under the radar, for 1980 was a year of escalating crisis in the Olympic Movement.

American President Jimmy Carter had called for a boycott of the Moscow Olympics after the Soviet invasion of Afghanistan. The United States ,Canada, Japan and West Germany were among nations not to travel to Moscow.

"The World Games is not being helped by the boycott," World Games executive director Hal Uplinger complained.

"Anything that detracts from sports, detracts from the World Games too.

"At our Opening Ceremony next year, the athletes will march in by sports not by nations. There will be no flags, no anthems."

Uplinger, a former professional basketball player, made another announcement.

"All the Olympic sports are eligible. Soccer said that if you excluded Olympic sports from the World Games, you would be doing to those sports what the Olympics had done to you," Uplinger confirmed.

International Olympic Committee (IOC) President Juan Antonio Samaranch had made his own sporting breakthrough in roller hockey and was a supporter of the World Games, but official IOC documents reveal his concern. There should be "no duplication with the Olympic Games", Samaranch insisted.

Keller’s own relationship with the new IOC leader was difficult. My insidethegames colleague David Owen, author of a superb biography of Keller, describes their "terse meetings" in the build-up to the World Games.

There was opposition from prominent Soviet officials, International Gymnastics Federation official Yuri Titov and IOC member Vitali Smirnov who described them as "in opposition to the Olympic Movement".

Smirnov was concerned that the Amateur International Boxing Association (AIBA) had signed up for the World Games. When AIBA executives met in the East German town of Halle, in the months leading up to the event, secretary Karl-Heinz Wehr, himself an East German, reported that they "decided unanimously to withdraw from the World Games."

Even so, pictograms in the original World Games emblem still included boxing.

Although organisers remained hopeful, the Eastern bloc stayed away from Santa Clara.

There remained financial difficulties and it took the intervention of West Nally, led by marketing pioneer Patrick Nally, to ensure that the Games went ahead as planned.

The Opening Ceremony at the Buck Shaw Stadium was watched by 8,000 spectators on a sunlit afternoon.

There was a message from American President Ronald Reagan and Casey Conrad, executive director of the President’s Council on Physical Education was present to watch the parade.

In the tribune of honour were Keller, Kim and Palmer. Samaranch did not attend as he was instead attending the Association of National Olympic Committee meetings in Milan. The World Games in any case did not yet have Olympic patronage.

The athletes entered by sport rather than nation. The flag for bodybuilding was carried by none other than Arnold Schwarzenegger!

In his capacity as International World Games Association President, Kim told the athletes: "Our theme is sport for the sake of sport, and a total disregard for where an athlete comes from."

It fell to Keller to officially declare them open.

"I am very honoured to be invited as President of the General Association of International Sports Federations, where the idea of these Games was born, to declare World Games '1' open. A long life and lots of success."

Keller noted that "the athletes appreciated any opportunity of mixing with athletes from different sports, a possibility which had previously been denied to athletes whose sport was not on the Olympic programme."

With Keller present, it was appropriate that a team from Switzerland should be the first into World Games action.

They competed in tug of war, a sport which had been included in the Olympics either side of the First World War. It produced Switzerland’s only gold medal in Santa Clara.

It was significant that both athletes from both Chinas did compete albeit in different sports. A solution to a long-running dispute had been brokered between the nationalists of Taiwan, now known in sporting circles as Chinese Taipei, and the Communist mainland, designated as People’s Republic of China (PRC).

They dominated badminton where Zhang Ailing beat South Korea’s Hwang Sun-ai to win women’s singles gold. She partnered Liu Xia to win the women’s doubles. Chen Changjie beat Denmark’s Frost Hansen to win the men’s singles. Sun Zhian and Yao Ximing took the men’s doubles.

The New York Times reported that the victories "were warmly received by an appreciative crowd of 1500."

Three years later, the PRC team was enthusiastically received at the Los Angeles Olympics.

Chinese Taipei’s gold came from karateka Lin-Ching Ming in the men’s kumite.

Elsewhere, Germany’s Jurgen Kolenda, a 20-year-old physics student from Berlin, won four gold medals in fin swimming in an almost Phelps-like dominance.

Casting also produced a quadruple gold medallist in Steve Rajeff, described in fly fishing circles as a "gentle giant" and a respected rod designer.

As the Games ended, an air traffic controllers' strike at the airport caused delays. "Fortunately, most athletes left after the completion of their competition," World Games secretary Don Porter said.

Later that year GAISF heard a report on the Games.

"The problems were minimal in light of the competitive success of the first World Games," insisted Kim.

"We take pride in stating that as a sports festival, it was a very big success."

He also spoke at the IOC Congress held in Baden-Baden to reassure members. "It never was nor is, intended to conflict with existing Games."

The second World Games were eventually held in London in 1985, but it was not until the end of the decade that they really cemented their place in the sporting calendar. By this time, the growing friendship of Kim with IOC President Samaranch ensured that IOC support was forthcoming.