Copenhagen Plank

Move · Resistance Training · Movement, Typed Supps

There is no weight to add — the difficulty is set entirely by how far your support point is from your hip.

Stage by stage

Set-up (Lever length sets the dose): Support at the knee halves the effective lever compared with support at the ankle, and that distance is the entire loading variable.
During the hold (Adductors load isometrically): The adductor group of the top leg is the only structure able to hold the pelvis up, and it does so at relatively long muscle length.
Immediately after (Fatigue is highly local): Failure is felt specifically in the groin rather than the trunk, which is what distinguishes it from an ordinary side plank.
Months later (Adductor strength rises): Strength changes of the kind field-sport trials have linked to reduced groin problems develop over months of consistent work.

Muscles trained

Primary: adductors
Secondary: abs, obliques, shoulders

Intensity

3.8 METs (Calisthenics (e.g., push ups, sit ups, pull-ups, lunges), moderate effort).

Time to effect

Weeks: Noticeable improvement in how long you can hold the position, and often a progression from the bent-knee version toward the full straight-leg version.
Months: Measurable gains in adductor strength — the kind of improvement that field-sport research has tied to meaningfully lower groin strain rates.

Common myth

Groin strains are just bad luck and can't really be trained around. In reality: A widely cited study of Danish footballers found that regularly performing adductor-strengthening exercises like the Copenhagen plank was associated with substantially lower rates of groin injury in players, making it one of the better evidence-backed injury-prevention exercises in soccer and hockey.