Any Ironman event, whether a half or a full is a big achievement. Whatever your goal for the event, it is a good idea to have the cut off times in mind so you can adapt your training towards this and hopefully can avoid the dreaded did not finish (DNF).
Let’s have a look at how much time you have for each event and let’s also see how much time you have for each discipline, assuming you are maxing out your time.
In total, you have 17 hours to complete a full Ironman (for most races) and 8.5 hours to complete a half Ironman.
You may be thinking, that sounds good, I will take 3 hours on the swim, 11 hours on the bike, and run a 3 hour marathon, because running is my best sport. This, unfortunately, is not how the Ironman works. Each discipline has a maximum time that you must finish by to ensure that you do not either get pulled off the course or get a DNF (did not finish). The individual time restrictions are mainly due to road closure logistics and also to do with safety, especially in the swim.
An Ironman requires you to swim 3.8km (2.4 miles), bike 180km (112 miles) and run 42.2km (26.2 miles) which is the equivalent of a running a marathon.
You have a total of 17 hours from the start of your race to complete the Ironman
The official cut offs are, from the time that you start your Ironman:
Swim Cut-Off: 2 hours 20 minutes
T1: 2 hours 30 mins
Bike Cut-Off: 10 hours 30 minutes
T2: 10 hours 40 mins
Run Cut-Off: 17 hours or Midnight
Assuming that you use up your maximum time in each discipline, you have the following amount of time in each discipline:
Swim: 2h 20 mins (pace: 3:41mins/100m)
T1: 10 mins
Bike: 8h (pace: 22.5km/hour or 13.98 miles/hour)
T2: 10 mins
Run: 6h 20mins (pace: 9 mins/km or 14:29/mile)
A half Ironman is essentially half of the above. You have 8.5 hours to complete the half Ironman with the below official cut off times from when you start:
Swim: 1 hour 10mins
T1: 1 hour 20 mins
Bike: 5 hours 30 mins
T2: 5 hours 40 mins
Run: 8 hours 30 mins
Assuming that you take the full amount of time in each discipline, you will have the following about of time in each discipline:
Swim: 1 hours 10 mins (pace: 3:41mins/100m)
T1: 10 mins
Bike: 4 hours 10 mins (pace: 21.6km/hour or 13.4miles/hour)
T2: 10 mins
Run: 2 hours 50 mins (pace: 8:03mins/km or 12:57min/mile)