I'm not an expert, but I think I can help you. Let me know if this makes sense. So, as you know, isometric is exerting muscular force without there being movement (or change in the length of your muscles). And there are obviously different types of isometric exercises from a CNS/activation perspective, e.g. pushing against pins in the rack (overcoming isometric), holding a squat position (yielding isometric). I believe that 'ballistic' isometric exercises are basically overcoming isometric exercises for shorter duration effort, maximum intensity. I thought that iso-ballistic exercises on the other hand are typically explosive exercises with light weight preceded by an isometric phase .e.g. rest-pause jump squat.

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Height 5'7 Reach approx 7'0
BW @ 23 Jul 08: 145lbs (>13%bf)
Re-training start: Jul 08 (post injury+3 mths rehab)

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