It is summer, a time when many people who were sedentary all winter get outside and start being active again. While being active is great, many people become injured when they start playing new sports or ones they haven’t done in years. So, how safe are the various activities done by the typical weekend warrior?
I am personally interested in this question because this summer I am bicycling across the U.S. When people hear a middle aged man is pedaling alone 3,000 miles the first question they ask is, “Is it safe?” Given the near misses and one crash on loose gravel I have had so far this trip my inclination is to say no. Nevertheless, personal experience is no substitute for looking at actual data.
The U.S. Consumer Product Safety Commission is the government agency that gathers data and makes rules to help reduce the risk of injury or death when using equipment like a bike, golf club or even treadmill. They estimate that total damage, death and injuries from using faulty consumer products costs the U.S. more than $1 trillion a year.
They track the specific types of injury from every kind of sport and make this available online via the National Electronic Injury Surveillance System (NEISS). This database not only tracks sports injuries, but also injuries from contact with any kind of consumer product from ATVs to workshop tools.
The NEISS system has tracked injuries since 1979. It counts only injuries that resulted in a person ending up in a hospital emergency room. Injuries that people take care of at home or leave untreated are not counted.
The NEISS releases data in aggregate form and also as individual case records without people’s name or geographic location. For example, one of the first injuries reported in 2017 is a 21 year old white man who was boxing with a friend while drunk and went to the ER because he was punched in the face.
The overall NEISS data show that bicycling is indeed dangerous. About 455,000 cyclists ended up in the emergency room in 2017. However, other sports and exercise activities have even more injuries. There were half a million ER visits because of injuries received while playing basketball. Going to the gym is the most dangerous with 526,000 people injured using exercise equipment. Maybe all the bike riders, basketball players and gym rats should try something safer like horseback riding since that group only had 49,000 ER visits.
The problem with using aggregate NEISS data to compare the dangers of various sports and activities is that participation rates vary. One reason few people are injured horseback riding is that relatively few people do this compared to the large number shooting hoops in their driveway or at the neighborhood playground.
This problem can be overcome by using the Bureau of Labor Statistics’ American Time Use Survey (ATUS), which provides information on how much of each day people spend exercising. The data show only about one in five Americans got exercise in a typical day. The ATUS list does not match perfectly with the injury data, but there is a large overlap.
ATUS shows the most common types of exercise are walking and using exercise equipment and weights, which I consider going to the gym. Using the gym figures as a baseline it is possible to compute a participation adjustment figure for each sport. For example, the data show 2.5 times more people go to the gym on a typical day than play basketball. This means basketball injury figures need to be increased by 2.5 times to make a fair comparison of being hurt in the gym versus being hurt on the court.
What do the adjusted figures show? The most dangerous activity is no longer going to the gym. Instead, it is playing football. The second most dangerous activity is playing hockey. Unfortunately, for me bicycling stays in third place on the list.
Table: Dangerousness of Various Activities Based on ER Visits
| Activity | Original Rank | Adjusted Rank |
| Football | 4 | 1 |
| Hockey | 11 | 2 |
| Cycling | 3 | 3 |
| Soccer | 6 | 4 |
| Basketball | 2 | 5 |
| Baseball, softball | 7 | 6 |
| Equestrian sports | 10 | 7 |
| Rollerblading | 8 | 8 |
| Volleyball | 9 | 9 |
| Gym | 1 | 10 |
| Swimming, surfing | 5 | 11 |
| Racquet sports | 13 | 12 |
| Running | 12 | 13 |
The adjustment is not perfect because we should also adjust for the amount of time spent in the activity since the longer people spend doing an activity the more time they have to be injured. Nevertheless, the message is clear for those of you thinking about taking your bike out for a spin on a lovely summer day. Be careful out there.