Quick recap (if you want to read in more depth check out strengthening diagonals Part 1)

  • Our bodies use slings (combinations of muscles) to create energy efficient, complex movements, produce force and stay upright.
  • Strong slings make us stable, powerful and accurate.
  • Weak, disrupted or inhibited slings create compensatory movements, which leads to lacklustre performances, and nagging niggles.
  • Slings get weak for all sorts of reasons like overuse, injuries, sitting and restrictions.
  • Last time we introduced the POS.


So let’s look at its counterpart, the anterior oblique sling (AOS), a diagonal muscle sling which runs across the front of the torso connecting the shoulder to the opposite hip and continues down to the foot. Its purpose is to work with the POS to create and stabilise athletic, dynamic movement because one limbs (e.g. right arm) task is stabilised, counterbalanced or powered by its opposite complementing limb (e.g. left leg).

Remember the javelin thrower powering up through the left leg and hip to impart extra force to throw the javelin with the right hand, notice the diagonal again? As we’ve said many climbing moves (and tonnes of other important life movements) use diagonal slings.


Let’s take a look at how the AOS works during climbing:

The adductor (groin muscles) and internal oblique starts contracting when you begin driving your foot down into a hold and pushing through the leg; at the same time the pec muscles and external oblique fire up as you squeeze and pull on a hold with the opposite hand. These muscles contracting simultaneously creates tension across the abdominal fascia (the stuff that joins the two) counteracting the rotational forces. This creates a stable base which effectively dissipates and translates movement forces throughout the whole kinetic chain. A functioning AOS means we have greater power to get us moving biomechanically well in the direction we want, causing little to no wear & tear on any particular joint.

Having rehabbed many climbers there’s just as much weakness and disruption going on in the AOS! You’ve probably got your cannon (power) but we would still choose to fire it from a battleship over a canoe. Time to continue converting that canoe…

Strengthening the AOS helps all the muscles from the hand and shoulder down to the opposite hip and foot move freely with good kinetic sequencing. A wicked exercise for training your AOS stability and co-ordination, is the Horse stance.

  • Begin kneeling on the floor in a 4 point stance, with knees under hips and palms under shoulders,
  • Gently draw your belly button in and lift the opposite hand and foot just enough to slide a piece of paper under and maintain the position yourself,
  • Keep the body rigid (like a gymnast) throughout keeping the hips and shoulders level, spine still and minimise any drift left or right,
  • A dowel (or foam roller) along your back can really help you hold good alignment,


Begin with 10s holds each side for 6 reps, and progress to holding the arm and leg out (2nd progression). Once you can hold 10s each side for 6 reps in the horizontal position, try coming off your knees and on to your toes and forearms (3rd progression). For the very strong and experienced you can try either doing it on a swiss ball (4th progression, not for the fainthearted), or moving onto a crawl (5th progression, even tougher but you won’t fall off!).

Getting good at it:

  • Improves body tension and how well you stabilises forces, especially rotational ones. This transfers to compression prows, powerful latches, holding barn doors, and handling unexpected landing impacts.
  • Builds solid foundations of static and dynamic stability creating a base for training strength and power in bigger movements like pull ups, squats and lunges.
  • Enhances posture and reduces achy muscles, as it trains the neck, shoulder, torso and hip stabilisers all at once.


Live the Rock Life,