Below is a chart that shows the verbiage used to explain to your athletes what weight to use based on the % difficulty prescribed. 

95% - 100% Difficulty - Close to maximal effort. Leave 0-1 reps in reserve.

90% - 94% Difficulty - High effort. Leave 1-3 reps in reserve.
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​85% - 89% Difficulty - Medium-High effort. Leave 3-5 reps in reserve.
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​80% - 84% Difficulty - Medium effort. Leave 5-7 reps in reserve.
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​70% - 79% Difficulty - Pick a weight you can move fairly easily.
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​60% - 69% Difficulty - Pick a weight that feels like a warmup.
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