Although movement impairment in Parkinson’s disease includes slowness (bradykinesia), decreased amplitude (hypokinesia), and dysrhythmia, clinicians are instructed to rate them in a combined 0–4 severity scale using the Unified Parkinson’s Disease Rating Scale motor subscale. The objective was to evaluate whether bradykinesia, hypokinesia, and dysrhythmia are associated with differential motor impairment and response to dopaminergic medications in patients with Parkinson’s disease. Eighty five Parkinson’s disease patients performed finger-tapping (item 23), hand-grasping (item 24), and pronation–supination (item 25) tasks OFF and ON medication while wearing motion sensors on the most affected hand. Speed, amplitude, and rhythm were rated using the Modified Bradykinesia Rating Scale. Quantitative variables representing speed (root mean square angular velocity), amplitude (excursion angle), and rhythm (coefficient of variation) were extracted from kinematic data. Fatigue was measured as decrements in speed and amplitude during the last 5 seconds compared with the first 5 seconds of movement. Amplitude impairments were worse and more prevalent than speed or rhythm impairments across all tasks (P < .001); however, in the ON state, speed scores improved exclusively by clinical (P < 10−6) and predominantly by quantitative (P < .05) measures. Motor scores from OFF to ON improved in subjects who were strictly bradykinetic (P < .01) and both bradykinetic and hypokinetic (P < 10−6), but not in those strictly hypokinetic. Fatigue in speed and amplitude was not improved by medication. Hypokinesia is more prevalent than bradykinesia, but dopaminergic medications predominantly improve the latter. Parkinson’s disease patients may show different degrees of impairment in these movement components, which deserve separate measurement in research studies.

Measurement of punch performance in a reliable, quantitative manner is relevant to combat sport, military, and concussion research. A punching protocol (3MPT) was developed, based on performance demands of amateur boxing, and evaluated on a custom‐built punch integrator (PI). PI reliability and accuracy were assessed by calculating TE and CV for a range of known masses. A within‐subject, repeated‐measures design assessed the test‐retest reliability of 3MPT. Fifteen male boxers (17.5 ± 0.5 years; 177.5 ± 9.5 cm; 73.0 ± 14.0 kg) were familiarized and then completed two 3MPT trials 90 minutes apart on 2 days (total of four tests). Peak punch force (N), relative punch force (N/kg), impulse (N·s), and rate of force development calculated to various time points were compared using a linear mixed model. Smallest worthwhile change (SWC) was also computed. PI data were reliable and accurate (CV <0.1%). TE and SWC comparisons revealed that 3MPT can detect moderate and large changes in performance; however, within‐day reliability improved from day 1 (3.1%‐13.8%) to 2 (2.3%‐5.1%) indicating a possible learning effect. Likewise, differences between test one and two were greater on day 1 than 2. Numerous punch‐related variables can be accurately and reliably measured using the 3MPT but repeat‐trial familiarization is suggested to reduce between‐test variability.

Dunn, EC, Humberstone, CE, Franchini, E, Iredale, KF, and Blazevich, AJ. Relationships between punch impact force and upper- and lower-body muscular strength and power in highly trained amateur boxers. J Strength Cond Res 36(4): 1019–1025, 2022—This study examined the relationship between upper- and lower-body strength and power characteristics and punch performance in 28 highly trained male amateur boxers. Punch performance was assessed with a custom-built punch integrator using a 3-minute maximal effort punch test that contained straight- and bent-arm punches from the lead and rear hands. Peak punch force and force-time variables including impulse and rate of force development (RFD; calculated to various points) were assessed. Force, power, and RFD of the upper and lower body were assessed with countermovement bench throw, isometric bench push, countermovement jump (CMJ), and isometric midthigh pull (IMTP) tests. Correlation and regression analyses revealed significant (p < 0.05) relationships between peak punch force and forces measured in CMJ and IMTP tests. In addition, peak punch force was moderately and significantly correlated to body mass, but RFD in the lower body was not. Moreover, no meaningful relationships between punch performance characteristics and any upper-body strength or power parameter were identified. The results of this study show that lower-body strength but not RFD had a moderate to strong positive and significant correlation to peak punch force production. Although upper-body strength and power are expected to be important in boxing, they did not discriminate between boxers who punched with higher or lower peak force nor were they correlated to peak punch force. Training that improves lower-body strength without increasing total body mass (to maintain weight category) may positively influence punch capacity in highly trained amateur boxers.