loris bertolacci

Physiological Analysis of Roller Derby at Game 1 VRDL

On Saturday night I went to the Showgrounds and watched Round 1 of the VRDL Roller Derby season. I have done some preliminary fitness testing with the girls at our centre in Preston, Melbourne. Advanced Athletes Performance. I found that most of the girls had reasonable Vertical Jumps using a Vertec. Some close to or above 50cm. So nothing amazing but ok.  The Average so far of about 12 girls is 43cm. I did some other tests such as long jump one and two legs and some side to side jumps t look at single leg differences. I also did the YO YO Intermittent Recovery test Level 1 to assess their general intermittent sport metabolic fitness levels. A few girls were above 15 which is ok. Others were below 14 which is poorish. But how specific is off Roller Derby training? Is there a need for repeat effort testing done speciically? One girl I tested was quite down in Jumps & Power test but performed really well on Saturday. i didnt expect it so that reflects the high skill level required here. But all things being equal in all sports, everyone can play at the highest level so fitness becomes a priority.

A lot of the girls are right into different fitness pursuits so I have been interested in what it takes to perform at the Highest level in this sport. Some I think do too much “fluffy” stuff. Is it power or a mixture of endurance and power and strength. What do the “best” players get in these fitness tests and is there any correlation at all between the tests and ability given adequate skill levels. I watched the US girls last year from Texas and some looked really conditioned and strong, some were massive and most looked pretty fit. Where will this sport head fitness wise? Guess is power and repeat speed and grunt!

So I put a Heart Rate monitor on Miss Chivas from the Rock Mobsters  and simply wrote down when she did some efforts and then looked at the download. Now as we know Heart Rate is a pretty poor reflection of the physiological demands of Roller Derby. Lots of sports science gadgets now exist that give insight into impact forces, acceleration patterns etc but hey this is a start. That will come.

Do some fitness tests. Add some skinfolds Sum 7. Watch a match. Do some RPE ( Perceived Exertion Data) analysis and then make some initial assumptions. In the end what I am trying to do is work out what the best approach to Strength and Conditioning and Fitness for Roller Derby is. It is a growing sport. Is there a need for lots of strength and conditioning? I will report on the RPE data next article and explain how to use this in training and competition.

Miss CHivas in the first half did heaps of  Jamming ( at back and trying to get through blocks!)  and one can see the same look on the heart rate curves that one see with interval training or even a football match. Look at the last part of Graph 1.  I dont know Miss Chivas’s maximum heart rate but assuming it is 200 then she was working pretty hard. The emotional side of heart rate analysis in games can add 20 bpm and interesting that it rarely went below 140 even at half time. Maybe rolling around instead of walking keeps the heart rate up? All assumptions at this stage.

The question is what is the cost of all the jostling and bumping? That can be measured and needs to be. That is why all thsi data needs to be correleted also with RPE data and then some acceleration & impact data.

In the second half the maximum heart rate was 187 and average was 156. A fair load IF her heart rate is 200. Watching the players when they come off after sustained efforts, subjectively they are stuffed.

The other question is IF a girl never ever will be a jammer how fit does she need to be? Does she need to squat 200kgs and be agile.Is an elite blocker a bit like a front rower in Union? Very big, very strong and capable of sustained hard ( if not fast) work.

BUT at the international level in future when superfit lean, hard Roller Derby OZ girls try and smash the US ladies I think the Jammers will have to be superfit and super powerful. Have a look at the last part of the graph for the first half below and simply look at the sustained work Miss Chivas did with multiple Jams. Phew. Heart rate max 193 (might be her max-who knows until we do a max test) and just up there for workrate wahtever the sport given she is a fit girl. Add bumps and twists and turns and quite a body load.

Look at sustained efforts in last part of graph below! I think 8 repeated jamming efforts ( is that the right word?). This Heart Rate analysis below is the first half plus warmups and meetings etc. Long day at office!

Heart Rate Download of  the Second Half. 3 fast jams at end.

A picture tells it all and here we see pics of Miss Chivas accelerating low an fast and below Ber Zerker getting low and strong and seeing how balanced the other girl is. Tough sport!

February 19, 2012 - Posted by Loris Bertolacci | Uncategorized