2015 USATF Outdoor Champion Jared Schuurmans says; The rim weight of the discus is relative to comfort and skill level. Low rim weight discus doesn't necessarily go far and high rim weight discus are not guaranteed to go further. Finding a weight that is comfortable to the athlete and his skill level is the best chance in optimal distance.
Low rim weight discus in theory are designed for beginners and as the weight goes up the logic is the discus will spin faster. Making it more aerodynamic and carrying the ability to go further. However, if the athlete does not have the ability to spin the discus well in a higher rim weight, will result in a reduced distance because the discus will wobble and create drag.
2016 USA Olympian Tavis Bailey says:
I wouldn't say its as much distance related for all of the discus'. Some of them are preference, skill and experience.
70-80-90 would be Novice - Intermediate - Advanced and the distances that come with that are relative to ability levels.
As well, another factor that plays into this tremendously, is ability to throw a clean discus. I know advanced 200 foot throwers that can't hit a super clean throw, so instead of using a 90+ they use 80-85.
I would recommend any thrower that is seriously looking to get some good throws to start with an 80+ and then move up from there. I have thrown many 200 foot throws in training and competition with that rim weight.
Lastly, I would say that a thrower MUST be loyal to a discus. When I was younger I got caught up with the technology of different discus and rim weights and threw different discus' at meets. I carry two different rim weight discus' to meets and won't warm up with or touch anything else on competition day.
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