posting the rule I found:
RULE 241
MEDICAL AND REFRESHMENT SERVICES FOR ROAD EVENTS
1. The organizers of road races should provide appropriate medical and refreshment
services for all competitors.
(a) Medical examinations - A hands-on medical examination during the progress of
an event by designated medical personnel clearly identified by the organizers
shall not be considered assistance.
(b) Adequate first aid facilities should be available.
(c) A competitor must retire from a race immediately if directed to do so by a duly
authorized member of the race medical staff. See Rule 144.4(c).
2. Drinking / Sponging and Refreshment Stations
(a) Water and other suitable refreshments shall be available at the start and finish of
all races.
2019 USATF Competition Rules - 135
(b) For all events, water shall be available at suitable intervals of approximately 5km.
For events longer than 10km, refreshments other than water may be made
available at these points.
NOTE 1: Where conditions warrant, taking into account the nature of the event, the
weather conditions and the state of fitness of the majority of the competitors, water
and/or refreshments may be placed at more regular intervals along the route.
NOTE 2: Mist stations may also be arranged, when considered appropriate under
certain organizational and/or climatic conditions.
(c) Refreshments may include drinks, energy supplements and/or foodstuffs. The
Organizing Committee will determine which refreshments it will provide based
on prevailing conditions.
(d) The Organizing Committee may permit athletes to provide their own
refreshments, in which case the athlete shall nominate at which stations they shall
be made available to the athlete. Refreshments provided by the athletes shall be
kept under the supervision of officials designated by the Organizing Committee
from the time that the refreshments are lodged by the athletes or their
representatives. Those officials shall ensure that the refreshments are not altered
or tampered with in any way. In National Championships of 20k and longer, the
Organizing Committee shall make provisions for the collection and distribution
of personal refreshments for those competing for the championship, as
determined by the Games Committee.
(e) The Organizing Committee shall delineate, by barriers, tables or markings on the
ground, the area from which refreshments can be received or collected. It should
not be directly in the line of the measured route. Refreshments shall be placed so
that they are easily accessible to, or may be put by authorized persons into the
hands of, the athletes. Such persons shall remain inside the designated area and
not enter the course nor obstruct any athlete. No official shall, under any
circumstances, move beside an athlete while he is taking refreshment or water.
(f) An athlete may at any time carry water or refreshment by hand or attached to his
body provided it was carried from the start or collected or received at an official
station.
(g) A competitor who collects refreshment from a place other than a refreshment
station is liable to disqualification by the Referee.
NOTE: A competitor may receive from or pass to another competitor refreshment,
water or sponges provided it was carried from the start or collected or received at an
official station. However any continuous support from a competitor to one or more
others in such a way may be regarded as unfair assistance and warnings and/or
disqualifications as outlined above may be applied.
(h) For Mountain, Ultra-Marathon, and Trail Races, athletes may receive
physiotherapy (massage, etc.) at official stations. This may be done by personal
representative