Get more from Russ: Fitness Instructor and leading Personal Trainer Russ Howe PTI reviews Grenade .50 Calibre, the new preworkout supplement from the company with last year's best-selling fat burner - Grenade Thermo Detonator. br br Is this preworkout intensifier as good as their first supplement? br br Today's review looks at the facts (ingredients) and it's effectiveness to give you the most comprehensive, scientific, results-driven review available on the supplement from one of the UK's leading personal trainers.