While Informative, South Korean COVID-19 Study Has Limited Applicability

COVID-19 is a novel disease. Basically, that means before emerging in the latter months of 2019, no one had ever identified it. Because COVID-19 is so new, what we know about how it spreads, its long-term effects, and how to treat and prevent it are continuously evolving.

Quality research into how—and where—COVID-19 transmission primarily occurs is still slowly emerging.

Insufficient Data Should Not Drive Health and Economic Policy Changes

In mid-May, the journal Emerging Infectious Diseases published an early release of an article examining the transmission of COVID-19 cases through a dance fitness instructor seminar and subsequently in fitness facilities across South Korea. The study, “Cluster of Coronavirus Disease Associated with Fitness Dance Classes, South Korea” has been widely reported in the media, and has caused some policymakers to delay or suspend the reopening of fitness facilities.

Even though the social and environmental factors that existed when the transmission outlined in this study occurred are highly unlikely to be recreated in reopened health clubs, news articles—and policymakers—continue to cite this article.

The guidelines and regulations in place by health authorities for fitness centers and the general public, as well as numerous examples of club reopening plans emphasizing social distancing and cleaning procedures, demonstrates the unlikeliness of these factors.

This study does provide some useful information on the transmission of COVID-19 in group exercise classes, and certainly contributes to our understanding of how COVID-19 spreads, but it does not provide sufficient evidence on which to largely base health and economic policies.

3 Issues with the "Cluster of Coronavirus Disease Associated with Fitness Dance Classes, South Korea" Study

When using this study to decide whether gyms and fitness centers should be open, the following issues must be kept in mind:

1. The timeline in which researchers identify cases in this study largely predates the extensive social distancing and other safety protocols subsequently adopted.
2. The study points to several key factors for COVID-19 transmission, which the vast majority of fitness facilities have already modified.
3. The study itself indicates that safety protocols and lower intensity activities may largely mitigate the risk of COVID-19 transmission.

1. The timeline in which researchers identify cases in this study largely predates the extensive social distancing and other safety protocols subsequently adopted.

The study uses data from February 15 through March 9. Officials would later trace COVID-19 cases back to a nationwide dance fitness instructor workshop held on February 15.

Two crucial things stand out about this timeline:

1. The workshop took place a full two weeks before the Korean Centers for Disease Control (KCDC) first recommended social distancing measures on February 29, and
2. It was more than a month before officials forced gyms in South Korea to close on March 21.

We know that COVID-19 is most easily spread in situations where people come into close contact with one another for prolonged periods indoors. The environment that facilitated the original spread of cases documented in this study—a four-hour-long in-person training seminar without any social distancing protocols, tightly packed and indoors—is no longer taking place, and won’t be for the foreseeable future.

Additionally, the closely packed dance fitness classes during which infected instructors came into contact with students—are also highly unlikely to be recreated in reopened fitness facilities.

In fact, the initial exposure at the instructor training and several subsequent exposures in group fitness classes were not on par with industry practice, outlined in ACSM’s Health/Fitness Standards and Guidelines, 5th edition, that each student or piece of equipment in the facility should be allocated 40-60 square feet (3.7-5.6 square meters). Given the measurements of the group exercise studio at these facilities provided in the study, any class with over 16 participants would not meet these guidelines; according to the study, some classes had as many as 22 people.

The extensive reopening guidelines enacted by health authorities and facilities themselves support this assessment.

2. The study points to several key factors for COVID-19 transmission that the vast majority of fitness facilities have already modified.

These factors include dense population, small space, and workout intensity. While true that traditional operations in pre-COVID-19 fitness facilities may have facilitated transmission, clubs have long since transformed those operations.

To solve the issues around dense population and small spaces, many state and facility guidelines limit capacity, sometimes by as much as 50-75% thereby reducing crowd density and allowing for six or more feet of social distancing inside the facility. Capacity limits help ensure social distancing is maintained, even at smaller facilities.

Health clubs encourage social distancing using barriers, floor markings, rearranging equipment, and signage. Many gyms provide large, open spaces for members to work out and have adopted a variety of strategies to eliminate close contact. Some smaller spaces within those facilities like saunas, locker rooms, and shower areas are closed or altered to reduce capacity and maintain social distance.

Workout intensity has also been a concern, with many hypothesizing that higher intensity exercise can promote transmission by spreading more respiratory droplets further in a space. However, many things done inside a fitness facility, including strength training, light aerobic exercise like walking, stretching and mobility, and yoga are lower intensity and typically do not lead to heavier breathing. Now, workout areas in health clubs provide room for social distancing, and many clubs have kept group exercise classes virtual until later phases of reopening.

Other factors like cleaning—for which gyms have enacted extensive protocols—and face coverings can help mitigate spread. Here are five examples of safety policies we see clubs enforcing:

1. adding cleaning responsibilities to every employee's job description,
2. implementing new technologies like electrostatic sprayers,
3. upgrading cleaning solutions,
4. cleaning more often, and
5. posting signage encouraging members to use good cleaning and hygiene practices.

3. The study itself indicates that safety protocols and lower intensity activities may largely mitigate the risk of COVID-19 transmission.

According to the study, secondary transmission of COVID-19 was seen in classes with five to 22 participants, in a 60 square meter room, during 50 minutes of intense exercise. No cases were documented in classes with fewer than five participants in the same space.

If we do the math, five people in a 60 square meter room—roughly 645 square feet—provides each participant about 12 square meters—or 129 square feet—of space. To break it down further, that's approximately an 11.5 x 11.5 foot—or 3.5 x 3.5 meter—section.

If gyms mark off spaces, giving at least 6 feet of distance between people exercising within their allotted space at any time, they would need a 12 x 12 space. This exceeds the degree of social distancing which appears safe according to these results.

What this Study Is Missing

This study also leaves out a major piece of information that prevents researchers from fully understanding the risk of contracting COVID-19 in a fitness center.

How many people attended the referenced fitness classes?

Reporting that 54 out of 60 group exercise attendees contracted COVID-19 from their instructors is extremely different than 54 out of 500 attendees. The study does not say what percentage of total class attendees these 54 people represent.

We know that 54 fitness class students contracted COVID-19 from their instructors, while the other 58 cases associated with the study contracted COVID-19 from those students in the home, socially, or in the workplace. This missing information would help us understand the risk of spread in group fitness classes compared to other public spaces.

Bottom line: It would be short-sighted to close—or keep closed—all aspects of all fitness facilities, especially those that provide low-intensity and well-spaced activities, weightlifting, or socially distanced sports like tennis, due to one study.

Even more so, when that one study details transmission resulting from one specific type of fitness service that gyms provide. Simultaneously, ignoring the many benefits gained from the wide variety of things you can do in a fitness facility to improve your health while still avoiding the factors that this study outlined as appearing to facilitate transmission.

Health and Fitness Centers Deemed Medium Risk, with Room to Lower Risk

The Johns Hopkins Center for Health Security designated health clubs to be at medium risk level based on three factors:

1. Contact intensity: how close you are to others and for how long,
2. Contact number: how many people you are in a place with, and
3. Modification potential: how much you can implement measures to mitigate the risks associated with the other two.

Certain characteristics and situations encountered in a typical fitness center experience prior to early 2020 could have been conducive to COVID-19 transmission. These are things like shared equipment, crowded group classes, and working out in close proximity to others, but as the Johns Hopkins guidance notes, that risk was of medium level, and clubs have the potential to modify those risk factors in order to create a lower risk environment, which gyms have done extensively around the globe.