Curling Season: Knees, Hips, and the Delivery

Curling clubs across Winnipeg are opening their ice this month, and with them comes a specific set of complaints: the knee that aches after a game, the hip that stiffens in the hack, the back that protests on the drive home. Curling has a reputation as a gentle sport, and in terms of impact it is. But the delivery is a demanding movement, and most curlers do it 16 times a game, several games a week, for five months.

This post looks at why the delivery loads the knees and hips the way it does, what the limited research tells us, and what helps.

What the delivery asks of the body

Break the delivery into its parts. The curler sets up in the hack, rises into a backswing, then drives forward into a long slide, with the sliding leg tucked into deep knee and hip flexion, the trailing leg extended behind, and the trunk bent forward and twisted toward the broom. The position is held, balanced on a slick sole, while the stone is released.

A review of the sport science of curling describes the delivery as a sprint-start push from the hack combined with a deep lunge, held through the slide.¹ Mechanically, that means:

• The sliding knee sits in deep flexion under load, placing high compressive stress on the kneecap and the front of the joint.
• The sliding hip is in deep flexion with the knee driven toward the chest, a position that irritates hips with limited range or impingement-type anatomy.
• The trailing hip is extended and rotated, loading the hip flexors and groin on the way down and asking them to hold a long lever on the way through.
• The trunk is flexed and rotated, loading the low back, particularly in curlers who get their rotation from the lumbar spine rather than the hips and thoracic spine.

Then there is sweeping: a hunched, rapid, repetitive movement that loads the shoulders and upper back.

What the research shows

Curling has not been studied nearly as much as hockey, but the available data fit the mechanics. A survey of competitive curlers in the United States found the knee was the most commonly injured region, followed by the back and shoulder, with most injuries overuse-related rather than traumatic.² Falls on the ice happen, and every club has a story about one, but they are the minority of the problem.

The age profile matters too. Many curlers are in their 50s, 60s, and 70s, and some knee or hip osteoarthritis is common at that age whether or not you curl. The question is not whether the joint is pristine; it is whether the sport is being loaded in a way the joint can tolerate.

Why the sliding knee complains

The most common complaint we see is pain at the front of the sliding knee, usually worst getting into and out of the delivery and when climbing stairs afterward. This is typically patellofemoral pain, which we have covered in a separate post. In curlers it tends to reflect three things: deep knee flexion under load, a quadriceps and hip not strong enough to control that position comfortably, and a sudden increase in volume at the start of the season.

For curlers with established osteoarthritis, the same principle applies. Exercise is one of the best-supported treatments for knee osteoarthritis, and the goal is to build the strength around the joint so that the load of the delivery becomes a smaller fraction of what the knee can handle.³ "Bone on bone" on an X-ray does not mean the knee cannot curl; it means the knee needs more capacity, not less use.

Why the hips complain

Hip pain in curlers shows up in two patterns. Pinching in the front of the sliding hip or groin at the bottom of the slide often reflects deep flexion meeting a hip with limited range. Pain on the outside of either hip, worse lying on that side at night, is often a gluteal tendinopathy, common in people over 50 and aggravated by positions that compress the tendon against the bone, such as deep lunging. A well-designed trial found that education plus progressive exercise outperformed a corticosteroid injection for this condition over the longer term.⁴

What helps

Build into the season. The first two weeks of league play after a summer off are reliably when problems start. Get on the ice a few times before league starts if you can, and treat the first few games as practice. No bad exercises, only too much too soon, and curling is no exception.⁵

Warm up properly. Most curlers walk in from a cold parking lot and step straight into the hack. Five minutes of easy movement (bodyweight squats, lunges, hip circles, trunk rotation) before the first end is one of the cheapest changes you can make.

Strengthen the legs and hips. Split squats, step-downs, hip hinges, and hip abduction work directly on the positions the delivery demands. Two short sessions a week through the winter is enough for most recreational curlers.

Work on hip and thoracic mobility. If rotation comes from the hips and upper back, the low back is spared.

Consider the stick. For knee or hip problems that are not settling, a delivery stick removes the deep lunge entirely while keeping you in the game. Nothing is lost by using it for a few weeks while the joint recovers.

If a knee or hip is not responding to these changes, or if pain is present at rest and at night, an assessment that looks at the whole chain rather than just the sore joint is worthwhile. You can read about how we assess sport injuries, curling included.

Curling is one of the few activities that people keep doing well into their 80s. The joints that get there are the ones that were kept strong along the way.

References

1. Bradley JL. The sports science of curling: a practical review. J Sports Sci Med. 2009;8(4):495-500.
2. Reeser JC, Berg RL. Self reported injury patterns among competitive curlers in the United States: a preliminary investigation. Br J Sports Med. 2004;38(5):e29.
3. Fransen M, McConnell S, Harmer AR, Van der Esch M, Simic M, Bennell KL. Exercise for osteoarthritis of the knee. Cochrane Database Syst Rev. 2015;(1):CD004376.
4. Mellor R, Bennell K, Grimaldi A, et al. Education plus exercise versus corticosteroid injection use versus a wait and see approach on global outcome and pain from gluteal tendinopathy: prospective, single blinded, randomised clinical trial. BMJ. 2018;361:k1662.
5. Gabbett TJ. The training-injury prevention paradox: should athletes be training smarter and harder? Br J Sports Med. 2016;50(5):273-280.