Coach, bodybuilder, and powerlifter Greg Doucette criticized DEXA scans in a recent video, questioning their status as the gold standard for body composition measurement based on personal experience and a 2019 study comparing DEXA and MRI. In response, Matt and Nick examine Doucette's points, exploring the accuracy of DEXA scans, their strengths and limitations, and how scientific literature should be interpreted regarding this imaging technique used to measure bone density and body composition.

Key Points

Greg Doucette criticized DEXA scans as the gold standard for body composition, citing personal experience and a 2019 study. Matt and Nick explore DEXA's precision and constraints while discussing how to analyse the scientific literature related to it.

• DEXA Scan Limitations: The podcast discusses the limitations of DEXA scans for measuring body fat, especially at extreme levels (e.g., very low body fat), where accuracy may decrease.
• Accuracy vs. Precision: The hosts explain the difference between accuracy (how close a measurement is to the true value) and precision (how consistent repeated measurements are), emphasizing that a tool can be precise but not accurate.
• Human Judgment in Bodybuilding: The podcast contrasts the use of DEXA scans with subjective judgment by experienced bodybuilding coaches, who sometimes trust their "laser eye vision" over DEXA results, particularly in highly trained individuals.
• Skepticism of Science: A recurring theme in the discussion is skepticism toward certain scientific studies, with some fitness personalities arguing that half of studies are unreliable, though this viewpoint is critiqued as intellectually dishonest.
• Pragmatism in Measurement Tools: While MRIs may be more accurate for measuring muscle mass, the podcast highlights the practicality of DEXA scans due to their accessibility and cost, despite some limitations.
• Personal Experience and Measurements: The hosts recount anecdotes where DEXA scan results conflicted with personal observations and mirror reflections, reinforcing the idea that DEXA is just one tool among many for assessing body composition.