Friday, April 3, 2015

Monday Morning Crew Chief, Friday edition: All about arm pump

UPDATE: After I posted this, my FB friend Mick Fialkowski informed me that Julián Simón had the same surgery by the same doctor, back in 2009, and that he's "as good as new" today. He warned me not to write Pedrosa off.  Simón won the last 125cc GP title in '09, and came close to winning the first Moto2 title in '10. He may indeed be as good as new, although he's now a 10th-place runner in Moto2, happy with a few points per race. He never showed his dominant 2009 form again, perhaps because he was physically incapable of running right at the front on the heavier Moto2 machines.

The MotoGP opener had more than one race's worth of drama; it's a shame no one saw it live, eh?

Post-race, it emerged that Pedrosa's arm-pump issues remain rate-limiting. Since all the usual surgical solutions have been tried, he's now in the same "let's-just-try-throwing-out-this-one-small-part-maybe-we-don't-need-it" club that Nicky Hayden's in. In Nicky's case it was a few small bones in his wrist; there are so many in there, could they all have a purpose? Surely those are just vestigial/disposable, like your tonsils or appendix. In Pedrosa's case, it was "dissecting and removing" the fascia (a tough, fibrous wrapping) around the muscles of his forearm.

Fascia are made of collagen and engineered to stretch primarily in one direction. They allow for some expansion of muscles as blood flows in when the muscle's exercising. But, once they're stretched to the limit, they can restrict additional blood flow. Hence, 'arm pump', which sports physiologists more accurately label, Chronic Compartment Syndrome.

Viz, Wikipedia:

Chronic compartment syndrome[edit]

When compartment syndrome is caused by repetitive use of the muscles, as in a cyclist, it is known as chronic compartment syndrome (CCS).
When compartment syndrome is caused by repetitive use of the muscles, as in a cyclist, it is known as chronic compartment syndrome (CCS).[10][11] This is usually not an emergency, but the loss of circulation can cause temporary or permanent damage to nearby nerves and muscles. The cause of compartment syndrome is due to excess pressure on or within the muscle compartments. This pressure can occur for many different reasons, many are due to injuries. Injuries cause the swelling of tissue. The swelling of the tissue forces pressure upon the muscle compartments, which has a limited volume. Due to this pressure, the venules and lymphatic vessels that drain the muscle compartments are compressed, and are prevented from draining. As arterial inflow continues while outflow is decreased, the pressure builds up in the muscle compartments. This pressure will eventually decrease the amount of blood flow over the capillary bed, causing the tissue to become ischaemic. The tissues will release factors and will lead to the formation of edema.
'Ischaemic' means, oxygen-starved.

The normal treatment for this, which Pedrosa's already undergone, is a fasciotomy. You can look that up on Wikipedia, too, but I don't recommend looking at the pictures before lunch. The more radical approach that Pedrosa and his Spanish physician just tried, was essentially removing the fascia.


So, what remains to be learned is, essentially, was Pedrosa's fascia actually doing anything useful, before arm pump set in? 

Because motorcycle racing is very, very hard on your right forearm, which is tightly packed with the muscles required to flex/extend/stabilize your wrist under acceleration and braking, clench your fingers as while gripping the throttle and braking. If that fascia is an essential piece of that biological machine; if that part of your body's not working, that's your career as a MotoGP rider, done.

The upside to this is that there's increasingly talk of getting rid of brolly dollies in MotoGP. Pedrosa, tiny, perfect, and often pouting, will make a perfect umbrella boy.

But seriously, folks… I'm sure that Honda's done everything they can, to the motorcycle, to minimize stress on Pedrosa's arm. But the consensus among sports physiologists is that while different athletes have a different tolerance for the kinds of stresses that lead to arm pump, each person's response is consistent. That's why Pedrosa chose that dramatic, last-ditch surgical solution: because he knew that if his arm pump came back once, it would keep coming back.

By the way, it's happened to me. Not only does it hurt like hell and result in a dramatic decrease in fine motor control, I found myself wondering, Will the next braking zone be the one where I attempt to squeeze the brake and nothing happens? Or will I get to the turn-in point, wrench on the bars, and have my hand just fall off the grip? It was fucking scary, and I raced at half-speed, compared to Pedrosa.

Pedrosa's not the only high-level racer whose results and career have been limited by the problem, but I don't remember anyone else going to such surgical extremes to resolve it. For the record, I admit that  last year, when Nicky had his wrist surgery, I predicted it would be the end of his career. I was wrong; Nicky's letting his heart rule over his head again.

That won't prevent me telling you that this will be the last year for Pedrosa. Mainly because I don't think that he'll be willing to circulate at the back of the grid, clawing for a point here and there. Although years on shit bikes beat him down, Nicky fundamentally loves the riding. That's not something Pedrosa ever really projects; I don't think he's a guy who will ride for the sake of riding. (Marquez would, though.)

What I wish I knew was, has Honda tried to datalog Pedrosa vs. Marquez, specifically looking at the rider inputs, not their bikes' responses? David Emmett, any insight here? Obviously, they're capturing brake pressures and turn-in rates, but what about other factors, such as grip pressure?

I am sure that Pedrosa's sure he's tried everything in terms of adjusting his riding style, but in the absence of data, even he's just speculating. It's entirely possible his problem's physiological, not behavioral; I suppose he may have to work his tiny, Tyrannosaurus arms extra hard because he's too small for his body inputs to have much influence. (Yes, Keith Code, I am aware that body inputs have no influence. Whatever.)

Logging total rider effort/input in a scientific way would be a great project for someone like Dainese.

By the way… There was a little bit of "draft Nicky" chatter when it emerged that Pedrosa wouldn't race Austin. With the Aspar team sponsorship in shambles, and as a contracted Honda rider, the idea of putting an American on the factory bike in Austin seems like a no-brainer. I don't know exactly why it didn't happen, but I wonder whether Nicky himself even wanted it. Why submit yourself to an apples-to-apples comparison with Marquez? It's a recipe for embarrassment. 

1 comment:

  1. Mark,

    Interesting conjecture about Dani's motivation but you're wrong mate.
    Little Pedrobot has never sung from the mountains so to speak but don't mix up a quiet, maybe introverted personality with a lack of love for the sport. I can't think of another rider in the current generation that's dragged himself back from career destroying injuries so often to keep riding. Injury wise I reckon he has to be the unluckiest rider in motoGP; maybe the successor to Randy Mamolas 'fastest man to never win the championship' title.

    There's a Repsol promo poster for Pedrossa that reads:
    "Si no fuera piloto, hafria querido ser ... piloto'
    I'll let you plug it into google translate but It should be a T-shirt I reckon.

    Congrats on the blog by the way. I only found it tonight and enjoyed (if not entirely agree) with your thoughtful discourses.