Performance Sport Care - Douglas F. Cancel, DC

09/03/2026

Jumper's knee usually is not bad luck. It appears when training climbs faster than the tendon can build up to handle it.

A tendon adapts, but slowly. Training volume can double in a week; capacity cannot. Where those two lines cross is where the pain begins.

Here is the part that catches almost everyone. Pain and healing run on different clocks. Pain quiets down first, often within a few weeks. The tendon needs considerably longer to recover its strength. Stopping when it stops hurting is the most common reason this returns.

That is not a discipline problem. Pain is the only signal you can actually feel, and it goes quiet while the work is still unfinished.

What sets it off: a sudden jump in practice or jump volume, going straight back to full training after time off, heavy squats stacked on high jump volume, limited ankle flexibility, and not enough recovery between sessions.

What lowers the odds: build jump volume in steps rather than leaps, keep track of how many jumps are in a week, work on ankle flexibility, practise how you land, and keep going after the pain stops.

Coming back too fast is the most common reason it returns. Capacity has to be rebuilt before the load goes back on.

09/01/2026

If the same injury keeps coming back, you may be fighting with one hand tied behind your back.

Your body uses food for two jobs. Fuel for training is the loud one. Repair and growth — bone, tendon, hormones, immune function — is the quiet one.

When training demand rises and eating stays the same, the loud job wins. The body meets the demand in front of it and draws against its own tissues for the rest. Repair gets cut first, and nothing about it appears on a standard exam. Which is why care aimed at the sore spot can work and still not hold.

Across 6,118 athletes in 46 studies, nearly 45% were not eating enough for their training load. Most were not dieting. Training demand rose. Eating stayed the same. It is arithmetic, not poor motivation.

Not every recurring injury is this — load errors and incomplete rehabilitation are more common. But it belongs on the list.

If someone you know has been treated for the same injury more than once, share this with them.

08/28/2026

You rested it. You iced it. The brace helped for about two weeks. Then you walked 36 holes over a weekend and the pain came right back.

Rest can quiet irritated tissue. It does not change why that tissue was taking more load than it could handle. In golf, the place that hurts is not always the place that started the overload.

Every swing sends force from the ground through the hips and trunk before it reaches the club. When one link cannot rotate or stabilize enough, another link takes the extra work. A common pattern: limited rotation in the lead hip shifts demand onto the lumbar spine, which is built to bend far more than it is built to twist.

Walnut Creek golfers load that chain in different ways: walking Boundary Oak twice a week, or stacking shorter rounds at Diablo Hills and Rossmoor.

New article on why the same golf injury keeps returning, and what actually has to change:

You rested it. You iced it. You bought the brace, and it helped for about two weeks. Then the pain came right back.

08/27/2026

Not every sore knee is the same problem. Patellar tendinopathy, better known as jumper's knee, has a recognisable pattern.

Three findings point to it. Pinpoint tenderness at the bottom tip of the kneecap, felt with the knee straight and the thigh relaxed. Stiffness on standing up after sitting a while, which eases once you get moving. And pain on a slow single-leg squat with the heel raised.

There is usually little warmth or puffiness around the knee, and that detail helps separate it from other causes of front-of-knee pain.

It turns up most in volleyball, basketball, CrossFit and weightlifting, and in sprinters and jumpers. Two risk factors show up again and again: a sudden jump in training volume, and limited ankle flexibility.

These findings suggest a pattern rather than a diagnosis. An examination is what rules the alternatives in or out.

The reason to catch it early is simple. With proper management there is a real chance of healing. Ignored, it may not have that chance.

Share this with an athlete who has been calling it a sore knee for a while.

08/25/2026

When people hear that an athlete is not eating enough, they assume an eating disorder. Usually that is not what is happening.

Researchers screened 464 adolescent athletes. Thirty met the criteria. Of those thirty, 80% showed no signs of disordered eating and did not report wanting to lose weight. They still had lower bone density than their peers.

What happened instead is arithmetic. A season started, or a second sport was added, or a growth spurt arrived. Training demand rose and eating stayed the same. The body pays for training first and draws against its own tissues for everything else — bone, tendon, hormones, immune function.

What families tend to notice: performance has stalled, soreness lingers longer than it used to, illness becomes frequent, or a second stress injury appears.

One small study, all female, so other groups will differ. But the pattern holds.

Fall season starts soon. When training goes up, food intake should follow.

Share this with a parent heading into the season.

08/24/2026

We explain what happens to the neck in different car crash scenarios and how we help people that have sustained injury.

After a Walnut Creek crash, a normal X-ray does not mean you are uninjured. 60-minute evaluation, supervised rehab, a clear endpoint. (925) 945-1155.

08/19/2026

Rest alone doesn't fix shin splints. Here's what the evidence says actually works.

Shin splints (medial tibial stress syndrome) are common and easy to ignore, but can lead to stress fractures. Assessment and treatment in Walnut Creek from Douglas F. Cancel, D.C.

08/19/2026

A 2022 systematic review examined five studies on the audible pop and pain outcomes. It found no evidence that hearing a pop was associated with greater pain relief.

That does not mean manipulation has no effect. Research shows that manipulation can be helpful for certain conditions. It means something much narrower: the sound itself is not a measure of whether the treatment worked.

In the full article, I explain what actually causes the pop, what the research says about it, and four questions worth asking before any manual treatment.

Read the full article:

A 2022 review found no link between the audible pop and pain relief. What the sound is — and what a sports chiropractor in Walnut Creek focuses on instead.

08/12/2026

Resting your jumper's knee doesn't heal it. Here's what actually works.

Persistent pain below the kneecap from jumping, squatting, or CrossFit training may be patellar tendinopathy. See how Performance Sport Care treats it.

08/11/2026

Why isn’t the injury getting better?

This graphic shows the common cycle: injury → try something → pain eases → injury returns. That repeating pattern is often driven by Relative Energy Deficiency in Sport (RED-S).

When energy intake falls short of training demand, the body economizes. Bone building and tissue repair are among the first systems cut. Nothing looks abnormal on a standard exam, yet the same tissues keep breaking down.

A 2024 systematic review of 6,118 athletes found nearly 45% had low energy availability—males at least as often as females. Most are not intentionally restricting. Training load simply increased while food intake did not.

Common questions we hear:

“But I’m not dieting—why would this apply?” → Because it’s math, not motivation. More training without more fuel leaves less for repair.

“Why does the injury keep coming back after it feels better?” → Local treatment calms the symptom. Without residual energy for rebuilding, the tissue never fully recovers.

At Performance Sport Care in Walnut Creek we look beyond the painful spot. We assess meal timing, carbohydrate intake, training-load changes, sleep, and injury history patterns so athletes actually have energy left for repair and growth.

Read the full post: performancesportcare.com/red-s-relative-energy-deficiency-in-sport/

If this pattern feels familiar, schedule an evaluation.