To maximize glute activation during a single-leg RDL, you must stretch horizontally (pushing the back heel and leaning the torso) while firmly anchoring your toes to the ground to create a stable base.

noli's read

The single-leg RDL is indeed a science-validated standard for glute recruitment. A comparative electromyography (EMG) study published in PMC demonstrates that this unilateral version outperforms the classic deadlift, particularly for activation of the gluteus medius, which must stabilize the pelvis. As for the importance of anchoring the toes, biomechanical research validates the concept of the "plantar tripod" as an essential foundation for the movement. Work on the "short foot" exercise (notably in the Journal of Bodywork and Movement Therapies) confirms that active foot stabilization triggers reflex co-activation of the hip and glutes. Nevertheless, presenting this movement as "the best" remains a shortcut: a systematic review by Neto et al. (2020) indicates that exercises like the step-up or the hip thrust generate even higher levels of gluteus maximus activation. Finally, the assertion that you cannot feel your glutes if the foot moves is a simplification, even if an unstable base does effectively reduce the ability to efficiently transfer force to the hip.

the sources

No named source held this one up — that absence is part of the verdict.