Defying geometric similarity: Shape centralization in male UK offshore workers

Applying geometric similarity predictions of body dimensions to specific occupational groups has the potential to reveal useful ergonomic and health implications. This study assessed a representative sample of the male UK offshore workforce, and examined how body dimensions from sites typifying musculoskeletal development or fat accumulation, differed from predicted values.

A cross sectional sample was obtained across seven weight categories using quota sampling, to match the wider workforce. In total, 588 UK offshore workers, 84 from each of seven weight categories, were measured for stature, mass and underwent 3D body scans which yielded 22 dimensional measurements. Each measurement was modeled using a body-mass power law (adjusting for age), to derive its exponent, which was compared against that predicted from geometric similarity.

Mass scaled to stature ^1.73 (CI: 1.44-2.02). Arm and leg volume increased by mass^0.8 , and torso volume increased by mass^1.1 in contrast to mass ^1.0 predicted by geometric similarity. Neck girth increased by mass ^0.33 as expected, while torso girth and depth dimensions increased by mass^0.53-0.72 , all substantially greater than assumed by geometric similarity.

After controlling for age, offshore workers experience spectacular "super-centralization" of body shape, with greatest gains in abdominal depth and girth dimensions in areas of fat accumulation, and relative dimensional loss in limbs. These findings are consistent with the antecedents of sarcopenic obesity, and should be flagged as a health concern for this workforce, and for future targeted research and lifestyle interventions.