Energy density: protein 4 kcal/g · carbs 4 kcal/g · fat 9 kcal/g.
Protein anchor: protein_g = weight_lb × coeff;
fat_g = weight_lb × coeff;
carbs_g = (target − P·4 − F·9) ÷ 4.
Goal defaults (g/lb): cut 1.0 P / 0.35 F; maintain 0.8 / 0.4; bulk 0.9 / 0.45.
Ranges follow ISSN position stand (Jäger et al. 2017) and Helms et al. (2014).
Preset ratios (C/P/F): balanced 40/30/30, low-carb 20/40/40,
high-protein 30/40/30, keto 5/30/65. The 70F/25P/5C alternative keto split is
available via "Custom".