Quick answer
Set the light first, then pose into it. Lengthen posture, create small gaps between limbs and torso, and use tension appropriate to the exercise or portrait.
Build shape with separation
Pressing arms flat against the body hides edges. A slight gap lets light outline the arm and gives the image a cleaner silhouette.
Use believable tension
Exhale, brace and hold a natural posture. Extreme contortions may define one area but make the whole picture look awkward.
Shoot small variations
Change chin, shoulder and hip angle slightly while keeping camera and light fixed. Review the series later instead of interrupting every frame.
Common questions
Should the light face me directly?
Direct frontal light is even but often flatter. Side or three-quarter light usually shows more shape.
Can editing replace good lighting?
No. Editing can refine contrast but cannot recreate natural direction and separation convincingly.