Sport climbing at the Tokyo Olympics is a combined competition that includes three disciplines: speed, bouldering and lead.

The aim of speed climbing is to scale a 15m (49 ft) high wall as quickly as possible. The speed wall is identical at all competitions. Each hold is the exact same size and shape and is placed in the same spot on the wall every time. This is in stark contrast to bouldering and lead climbing, where each route is unique, and athletes are not given any information about the routes until the competition begins. For speed climbing, though, athletes memorize the path up the wall and practice the ascent ad nauseum so that muscle memory takes over on competition day. Speed climbing is also the only Olympic sport climbing discipline that uses an auto-belay system for the athletes’ safety. 

At competition, two parallel speed walls – lane A and lane B – are placed beside each other. Athletes climb in pairs, starting simultaneously on the sound of a buzzer. A false start is declared when an athlete leaves the ground less that 0.1 seconds after the buzzer sounds, which accounts for the limit of human reaction time. A false start has different implications depending on the round of competition (see below). At the top of each lane is a touchpad that each climber must contact to stop the clock.  

A pair of sport climbing athletes race up the speed wall.

ADEK BERRY/AFP via Getty Images

QUALIFICATION 
Each athlete has two attempts (one on each lane) during the qualification phase to record the fastest possible time. Athletes are ranked, quickest to slowest, using each athlete’s best time. A false start on either climb, however, results in the athlete being ranked last in qualification. The climbers run in pairs for expediency but are not affected by the result of the adjacent climber’s ascent. 

FINAL 
During the eight-person final round, the speed climbing phase becomes a single-elimination tournament. Athletes are initially seeded 1-8 based on results of the qualification phase and face off in quarterfinal matchups consisting of 1 vs 8, 2 vs 7, and so on. Winners of the quarterfinal matchups advance to the semifinals, while losers face off for rankings 8-5. Semifinal winners advance to the final while losers face off for rankings 3 and 4. The winner of the final race is awarded the top ranking in the speed disciple, while the loser takes the #2 ranking. Times are largely irrelevant in this phase; as long as a climber ascends the wall quicker than his/her opponent, the exact time does not matter. 

The object of bouldering is to scale multiple short (4.5m, about 15 ft) but challenging routes, called “boulder problems”, with the fewest attempts in a given period of time. It is equal parts a mental and physical task, as athletes must have the strength and balance to use the holds, but also the intuition to understand how to manipulate their bodies to solve the problems. Prior to each round of competition, route setters design and set the problems, which are kept hidden from the athletes until the start of competition. Route setters usually try to test different aspects of the climbers’ abilities on each boulder problem. Unique boulders are set for men and women and are changed between the qualification and final rounds. No rope is used, but the floor beneath the boulder wall is heavily padded. 

Each boulder problem has a designated starting position which includes mandatory placement of all four limbs at the bottom of the wall. The uppermost hold is considered the “top” of the boulder. An athlete is determined to have topped the boulder when he/she places two hands on the top hold and maintains control long enough for a judge to give a signal that the ascent was successful. Between the starting position and the top of each boulder is a “zone hold”. A zone hold is an approximate midpoint on the route. A climber who manages to reach the zone hold but fails to top the boulder is awarded partial credit. 

At the end of the round, climbers are ranked based on most boulders topped, most zone holds reached, and fewest total attempts. To “flash” a boulder is to top it on a first attempt. Flashing every boulder in the round is difficult but can guarantee a climber the top rank.  

QUALIFICATION 
Four boulder problems are set for the qualification phase. Athletes get up to five minutes to complete each boulder, and an additional five-minute rest period before attempting the next boulder. Once the first climber has moved to the second boulder, the next climber begins their attempt on the first, and so-on. 

FINAL 
Three boulders are set for the final round. Unlike in qualification, the eight finalists begin the bouldering competition with a six-minute collective observation time, during which they can visually study all three problems but not attempt them. Afterwards, climbers return to the isolation room and emerge one-by-one to attempt the first boulder. Unlike in qualification, only one athlete climbs at a time during the final. 

Lead climbing tests similar abilities to bouldering but incorporates endurance as well. A unique route is set on a 15m wall. Each climber gets one attempt to ascend as high as they can on the route in six minutes. The climber that reaches the highest hold on the wall – or, if multiple climbers top the route, the climber that does so in the shortest amount of time – is awarded the top rank. In addition to ascending the route, lead climbing requires athletes to periodically clip their belay rope into several quickdraw carabiners installed along the route for safety. Failing to clip into a quickdraw invalidates any further progress a climber may make on the route.  

On a lead climbing wall, each hold is numbered from bottom (1) to top (the total number of holds present on the route). If an athlete falls along the route, it is recorded at which number hold they maxed out on. A climber that falls immediately after securing hold 34 is given a score, for the purposes of ranking, of 34. However, if the climber maintains control on hold 34 but falls reaching for hold 35, their score is 34+. This helps separate athletes that fall at the same spot on the route. 

In both qualification and the final round, the lead climbing competition begins with a six-minute collective observation period, during which climbers can study the wall without attempting it. Following the observation period, all athletes return to the isolation zone, and one-by-one emerge to attempt the climb. There are no rule differences between the qualification round and the final round.