Basketball

Is basketball safe?

Yes, for almost everyone who plays. Basketball has had two traumatic deaths in US high-school and college sport in 43 years of national records, one boy and one man. When basketball players die, it is nearly always the heart. On our estimate a high-school practice or game carries about 0.1 micromortsMicromortA one-in-a-million chance of death. It lets you compare the risk of very different activities on one scale.More in the glossary, in line with a session of football. For US college men the figure is higher, about 0.3 to 0.7 micromorts a session, because their rate of sudden cardiac death is the highest in college sport.

The common cost is injury: ankle sprains, knee sprains and concussions, with ACL tears a particular risk for women.

Why basketball has the highest cardiac death rate

A study of every death in US college sport between 2003 and 2013 found 79 sudden cardiac deaths across 4.2 million athlete-years. Men's basketball stood out at 1 death per 8,978 athlete-years, and 1 per 5,200 in Division I, more than ten times the average for all college athletes. Over a four-year Division I career that is a 1 in 1,300 chance. Male basketball players were more likely to die suddenly of a heart problem than in a car crash.

Women's basketball was far lower, at 1 per 77,061 athlete-years. The authors found no notable difference between black and white Division I players, which suggests something about the demands of the game itself. Male basketball players were about 15 times more likely than other male athletes to die of cardiomyopathy, a disease of the heart muscle, and two of the three deaths from Marfan syndrome, a connective tissue disorder linked to great height, were in basketball players.

High-school figures come from the National Center for Catastrophic Sport Injury Research (NCCSIR) at the University of North Carolina, which has tracked school and college sport since 1982. Boys' basketball has the second-highest count of exertional and medical deaths of any high-school sport after American football, 157 in 43 years, or 0.68 per 100,000 players a season. The NCCSIR relies partly on media reports and misses some deaths, so the true figure is likely a little higher.

How we worked out the micromorts

The college rate of 1 in 8,978 athlete-years equals about 111 micromortsMicromortA one-in-a-million chance of death. It lets you compare the risk of very different activities on one scale.More in the glossary a year. In the college study, 56% of sudden cardiac deaths happened during exertion and the rest at rest or in sleep, so about 62 micromorts a year are linked to playing. Spread over 150 to 250 practices, games and conditioning sessions a year, that is 0.25 to 0.4 micromorts a session; for Division I men it reaches about 0.7.

For high-school boys, 0.68 deaths per 100,000 players a season is about 7 micromorts a season. A season of about 90 practices and games gives 0.08 micromorts each. All of these are estimates. There is no good per-session figure for adults in pickup games, where coronary artery disease starts to matter from middle age.

How often basketball players get injured

US national surveillance from 2005 to 2014 recorded injuries that kept a player out for at least a day.

Games were two to three times riskier than practice. A high-school boy can expect a time-loss injury roughly every 650 sessions, a college player every 200 or so. Ligament sprains, muscle strains and concussions led at every level, and the ankle, knee and head were hit most. That is a lower rate than high-school American football, at 4.01, but basketball injuries are not trivial: an ACL rupture usually means surgery and close to a year out.

Women are hit harder by knee injuries. In US college basketball from 1990 to 2002, women had 405 ACL injuries against 115 among men, and about three in four happened without contact, on a landing, cut or sudden stop.

How to play more safely

1. Wear lace-up ankle braces if you play often. In a trial of about 1,460 US high-school players, they cut acute ankle injuries from 1.41 to 0.47 per 1,000 exposures, about two-thirds fewer, with or without a previous sprain.
2. Train landing and cutting. Neuromuscular warm-ups that teach soft landings with knees over toes are the best tool against ACL tears, especially for girls and women.
3. Know the warning signs. Fainting or near-fainting during exercise, chest pain, a racing heart or a relative who died suddenly before 50 all need a doctor's check before you keep playing.
4. Ask whether your school, club or gym has a defibrillator and an emergency plan, and learn CPR. A shock within 3 to 5 minutes is what saves most people in cardiac arrest.
5. Sit out after a head knock. Follow your league's concussion protocol and do not return the same day.
6. Wear a mouthguard. It protects teeth from elbows and heads in the scramble for rebounds.

How we scored it

Fatality risk (95) rests on about 0.1 micromortsMicromortA one-in-a-million chance of death. It lets you compare the risk of very different activities on one scale.More in the glossary per high-school session, the level most players reach; college men face several times more. Serious injury risk (60) reflects frequent sprains and concussions that rarely need hospital care. Controllability (65) is helped by braces and landing training, and limited by hidden heart disease. Rescue (90) is close in a gym with a defibrillator. Basketball sits just above football on our scale and well above rugby.