Using biomechanical feedback:
In this paper
, Paul Glazier argues that biomechanical feedback can describe an athlete’s current patterns of coordination and control, but cannot prescribe how these patterns should be modified to enhance performance (a topic we previously covered
in relation to simulation modeling). Instead, he suggests that the data be used to channel the athlete’s search towards their own unique ‘optimum’ pattern as they actively explore their perceptual-motor workspace during practice. A related systematic review
recently compared knowledge of performance and knowledge of results for promoting motor skill learning.
Do you normalise your biomechanical data (or any other data) by dividing by another variable such as body mass?If so, then you’ll probably want to read through a couple of recent Twitter threads. The first
(actually from a while ago) covers some assumptions such as linear relationships that pass through the origin, as well as consequences for data normality. The second thread
provides a bit more statistical insight into these considerations. On the topic of normalisation, this short communication article
discusses the various alternative methods for temporally aligning data (e.g.
to 0-100% of a movement).
Relative muscular effort during squats:
I really liked the way this paper
combined experimental and theoretical approaches. They used a musculoskeletal model to determine relative muscular effort during back squats ans split squats, accounting for force-length-velocity properties. A short Twitter thread summary
of the paper is also available.
Linking the CMJ force-time curve to performance: This paper
used an objective classification of countermovement jump ground reaction force profile (e.g.
uni- or bimodal, early or late peak, high to low or low to high) to explore relationships with performance measures including jump height and modified reactive strength index (RSImod). RSImod, but not jump height or take-off momentum, was greater in unimodal jumps, whereas take-off momentum and RSImod were both greater when peak force occurred early in the concentric phase.
As with some of the items mentioned last month
, I love to get an insight into the history of our discipline. This month, a couple of old extracts surfaced online. The first was the proceedings
of the American Society of Biomechanics’ 1st annual meeting in 1977. One example
mentioned the need for sports biomechanics to move beyond centre of gravity analyses and assess individual body segments. The second extract, shared
by Ross Miller, described the 500 man-hours required to perform 3D inverse dynamics calculations in 1950.