If a swimmer breaks, for instance, the 100-meter free stroke record in a medley event does that record count towards the hundred meters discipline or are those records held apart?
If a swimmer breaks a record in a medley event, does the record count towards the individual event or the medley event?
This is clear in the rules of swimming. For example, take the USA Swimming (official web site) rules, which follow from FINA. In section 102.24, Timing Rules one finds:
102.24 TIMING RULES
- Requirements for Official Time
A. Performance Requirements
(1) An official time can be achieved only in USA Swimming sanctioned or USA Swimming approved competition, or in an observed swim in accordance with all applicable rules. It may be achieved in:
(a) Any heat
(b) A swim-off
(c) A lead-off leg in a relay
(d) A split time recorded from the official start to the completion of an initial distance with a legal finish within a longer event, provided the swimmer completes the event or the lead-off portion of the relay in compliance with applicable rules.
(e) A time trial or a record attempt.
So, it must be a lead off-leg of the relays (such as Ryan Murphy's 100 back time at the 2016 Olympics). The freestyle portion of the medley relay is not the lead off leg, so that would not count. As a general principal, a relay start gives you about a 0.7 second advantage over a flat start (not firm science, just 40+ years of experience).
As noted in the comments, it is then also possible that the lead-off leg of an individual medley event (50 or 100 fly for the 200 or 400 IM) could also be an individual record. Similarly, although the OP specified 'medley', splits of longer races (i.e. 100 fly during a 200 fly, or 400 free during the 800 free) are also fair game for records.
Also, the reasoning behind this is that those who aren't swimming the leading leg are able to start moving (arm swings etc) on the block even when the previous person hasn't finished. The only requirement is some part of the swimmer's body must be touching the blocks as the previous swimmer finishes. Aug 24, 2017 at 11:07
USA Swimming teaches the 'toes to touch' method to officials - you watch the swimmer on the blocks leave (the toes part), and only then look down to the swimmer coming in (the touch). In theory, that gives a slight advantage to the swimmers on the exchange, in line with the overall referring philosophy taught. In the case of automatic timing systems, they too give leeway for the exchange. Aug 25, 2017 at 12:23
I was under the impression that it's also possible to set a record in the butterfly leg of an Individual Medley event for the same reason (it's from a fixed start) although this isn't made clear in the answer? Mar 21, 2018 at 16:20
@WillAppleby - good catch - I had assumed medley relay, but should have continued with the rest of the rule. I will edit accordingly. Mar 21, 2018 at 16:28
It's quite an interesting rule then, so in theory during a 1500m race you could break the 50, 100, 200, 400 and 800 records at the same time! I wonder if it's the same in running and other distance-based sports? Mar 22, 2018 at 11:49