The weight classes are defined in the AERC Rules:
8.5.2 There are also weight divisions within the Senior Division.
Competitors are recorded in weight divisions as indicated in the ride
results.
8.5.2.1 Heavyweight, consisting of riders whose combined body weight and
tack is 211 pounds or more.
8.5.2.2 Middleweight, consisting of riders whose combined body weight and
tack is from 186 to 210 pounds.
8.5.2.3 Lightweight, consisting of riders whose combined body weight and
tack is from 161 to 185 pounds.
8.5.2.4 Featherweight, consisting of riders whose combined body weight and
tack is 160 pounds or below.
8.5.2.5 For a rider to stay within a weight division he/she must meet the
minimum requirement but need not stay under the maximum parameter.
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