Elite triathletes change muscle recruitment off the bike
Following up on last week’s post about the increasing use of 3-D motion analysis, there’s a new Australian study examining the running stride of triathletes coming off the bike in this month’s Journal of Sports Sciences. They took “moderately trained” (i.e. club level) triathletes and measured their stride during a 30-minute, either with or without a bike ride beforehand, using EMG to measure muscle activation and motion capture to measure the stride.
The basic finding: 14 out 15 triathletes showed no difference in muscle recruitment between the two runs, but five of them did show kinematic differences (their joints were at different angles and moving differently). What’s surprising is that this is basically the opposite of what they found in a similar study of elite triathletes, who kept their stride pretty much constant but had different muscle recruitment patterns off the bike.
What this suggests is that it’s difficult to run “normally” coming off the bike, but elite triathletes have trained long enough to learn how to send different signals from their brain to their muscles in order to reproduce their normal stride.
Therefore [the authors conclude], training interventions focused on quickly restoring optimal running movement patterns after cycling may be advantageous for moderately trained triathletes’ performance.
The only problem: I’m not really sure what those interventions would be, other than doing your training in a 3-D motion capture system!
[Thanks to Steve Magness for the tip-off.]