Papers by Michel Ladouceur
Journal of the Endocrine Society
Objective Arthropathy is common in acromegaly (ACRO) and profoundly impacts patients’ quality of ... more Objective Arthropathy is common in acromegaly (ACRO) and profoundly impacts patients’ quality of life. The aim of this study was to compare joint pain score, usage of pain relief therapy and history of joint surgery between patients with history of ACRO and patients with non-functioning pituitary adenoma (NFA) who had previously undergone surgery. Methods Sex- and age-matched participants (n=34 for both groups) were recruited from the Halifax Neuropituitary Program to complete an online survey. All ACRO patients were in remission with or without medical therapy. An anchored visual analog scale (0-100 mm) was employed to assess joint pain, and additional questions assessed usage of pain relief therapy and history of joint surgeries. Demographic and joint pain data were compared using paired t-tests, whereas usage of pain relief therapy and history of joint surgeries were compared using exact McNemar's tests. Results Height and weight were not significantly different between the A...
This study investigated the changes in maximal overground walking speed (MOWS) that occurred duri... more This study investigated the changes in maximal overground walking speed (MOWS) that occurred during walking training with a functional electrical stimulation (FES) orthosis by chronic spinal cord injured persons with incomplete motor function loss. The average walking speed over a distance of 10 m was calculated while the participants (n = 14) used their FES orthosis with and without power as well as with the various ambulatory assistive devices available. Within the first year of use, walking with an FES orthosis facilitated use of more advanced ambulatory assistive devices (10/14), improvements in functional mobility (12/14) and increases in the combined (0.26 m/s) and therapeutic (0.25 m/s) MOWS that were correlated (combined: r = 0.57; therapeutic: r = 0.69) with their respective initial MOWS. A longitudinal analysis showed that increases in MOWS followed a pattern of changes best described by either an exponential association (8/12) or a linear (4/12) model. These changes were similar for the combined and therapeutic MOWS (7/11) as well as for the different ambulatory assistive devices (8/9). It is concluded that the increased MOWS during walking training using the FES orthosis is mostly due to a therapeutic effect, implying that mechanisms of plasticity occur during such a training paradigm.
Journal of Sports Sciences, 2021
ABSTRACT The study aimed to determine the pacing strategies of elite single-boat sprint kayakers,... more ABSTRACT The study aimed to determine the pacing strategies of elite single-boat sprint kayakers, as well as the relationships between stroke parameters (stroke rate (SR) and stroke length (SL)) and kayak speed throughout the race. High-resolution split speed and stroke parameter data from men’s (MK1) and women’s (WK1) single-boat A- and B-finals in 2016–2017 international sprint kayak competitions were analysed. Correlation coefficients were calculated between SR-speed and SL-speed during each split for each race group. Athletes followed all-out, positive and seahorse-shaped pacing strategies for the 200 m, 500 m and 1000 m races, respectively. SL-speed had greater correlations during the first half of the MK1 200 m race, whereas SR-speed had greater correlations during the second half. SR-speed correlations were greater than SL-speed correlations throughout the final 150 m of WK1 200 m races. There were large and very large correlations between SR-speed at the end of both the WK1 500 m and MK1 1000 m race distances, respectively, despite following different pacing strategies. Single-boat pacing strategies change due to race distance during major international sprint kayak competitions, whereas the relationships between stroke parameters and speed change depending on athlete sex and the race distance.
ISBS Proceedings Archive, 2021
The purpose of this study was to determine if stroke rate effects anteroposterior, lateral, and v... more The purpose of this study was to determine if stroke rate effects anteroposterior, lateral, and vertical forces on the kayak's footboard and seat. Participants (n=10), with a year or more of competitive kayaking experience, completed four 30-second trials on a kayak ergometer at different stroke rates (60 strokes per minute (spm), 80 spm, 100 spm, and maximum spm). Mean force, impulse, and impulse*stroke rate were identified for the footboards, and seat, separately within each trial (ten single strokes). Interestingly, both anteroposterior and lateral axes kinetic adaptations to stroke rate occurred on the left footboard whereas the right footboard presented only lateral adaptations.
ISBS Proceedings Archive, 2021
The purpose of this study was to determine if stroke rate effects anteroposterior, lateral, and v... more The purpose of this study was to determine if stroke rate effects anteroposterior, lateral, and vertical forces on the kayak's footboard and seat. Participants (n=10), with a year or more of competitive kayaking experience, completed four 30-second trials on a kayak ergometer at different stroke rates (60 strokes per minute (spm), 80 spm, 100 spm, and maximum spm). Mean force, impulse, and impulse*stroke rate were identified for the footboards, and seat, separately within each trial (ten single strokes). Interestingly, both anteroposterior and lateral axes kinetic adaptations to stroke rate occurred on the left footboard whereas the right footboard presented only lateral adaptations.
Journal of Biomechanics, 2022
The purpose of this research was to validate the use of a low-cost IMU system to measure upper-li... more The purpose of this research was to validate the use of a low-cost IMU system to measure upper-limb joint angles by comparing it to passive optical motion capture measures. Fifteen participants (five females; 25.9 ± 4.7 years) completed one trial of four simple range of motion (ROM) movements (elbow flexion/extension, shoulder abduction/adduction, shoulder flexion/extension, and shoulder internal/external rotation), and three complex functional daily tasks [hand to: back pocket (HBP), contralateral shoulder (HCS), head (HTH)]. Movements were measured, simultaneously, using fourteen OptiTrack cameras and five Notch® IMUs. The mean joint angle difference between devices ranged from 0.10° ± 3.11° for the HBP shoulder internal/external movement to 44.95° ± 3.50° for the simple ROM shoulder internal/external rotation movement. Nine of sixteen movement and plane comparisons showed significant differences between the device-specific movement cycle waveforms. Eleven of the comparisons showed either fixed and/or proportional biases (fixed only: 9; proportional only: 1; both fixed and proportional: 1). Due to multiple movements having large amplitude errors, low waveform similarities, and/or statistically significant mean differences between the Notch® IMUs and the gold-standard motion capture devices, we cannot recommend that Notch® IMUs are valid devices for measuring upper-limb joint angles during simple ROM and complex functional daily tasks.
The purpose of this study was to investigate pacing strategies used by elite flatwater canoe kaya... more The purpose of this study was to investigate pacing strategies used by elite flatwater canoe kayak sprint athletes in 12 Olympic events. Boat velocity data for canoe and kayak A-final races were extracted from the International Canoe Federation’s website for five major international competitions during the 2016 and 2017 seasons (n=374 boats; n=87 races). Principal component analysis was used to determine pacing strategies in 200, 500, and 1000 m races. Differences in pacing strategies between medalists and nonmedalists were found only in 1000 m races. These findings reflected overall differences in boat velocity but also the timing of changes in boat velocity throughout the 1000 m race. This research shows that certain pacing strategies are associated with more success in canoe kayak sprint during long duration races.
the tibialis anterior muscle when the triceps surae was relaxed. Regarding the stretch velocity d... more the tibialis anterior muscle when the triceps surae was relaxed. Regarding the stretch velocity dependency of the stretch reflex, stimulation significantly increased the velocity threshold and decreased the area under the velocity – reflex relation.
Sports Biomechanics
The aim of this research was to use principal component analysis (PCA) to investigate the current... more The aim of this research was to use principal component analysis (PCA) to investigate the current pacing strategies of elite canoe kayak sprint athletes and to determine if there are differences in pacing patterns between medallists and non-medallists at major international competitions. Velocity data collected using global positioning systems (GPS) from all a-finals of major international competitions in 2016-2017 (including canoe and kayak, single and crew boat, and male and female) were downloaded from the International Canoe Federation's website. Data were normalised by the average velocity within each race and organised by race distance. In total 10, 14 and 16 races were analysed, and they followed all-out, positive, and 'seahorse-shaped' pacing strategies for the 200 m, 500 m, and 1000 m events, respectively. Normalised velocity PC1 (p = 0.039, ES = -0.44) and PC2 scores (p < 0.001, ES = -0.73) for 1000 m races were significantly different between medallists and non-medallists; however, significant differences between PCs were not found between groups in shorter race distances (i.e. 200 m and 500 m). Data collected using GPS provide information that can be used to better prepare athletes for canoe kayak sprint races lasting between 30 s and 240 s in duration.
Occupational Ergonomics
BACKGROUND: Laser imaging provides an alternative to manual measurements in the collection of gen... more BACKGROUND: Laser imaging provides an alternative to manual measurements in the collection of general anthropometric surveys focused on 1-D measures. This study aimed to develop a systematic method of comparing manual and digital anthropometric measurements and validate a commercial three-dimensional laser scanner for anthropometric measurements. OBJECTIVE: The purpose of this preliminary project is to validate a laser scanner for selected length and girth measurements. METHODS: A variety of linear and circumferential segmental measures from 20 participants were either extracted from a 3D commercial laser imaging device scans or measured manually. Error between manual and scan-extracted measurements was compared based on ISO20685, and clinical standards. Regression analysis improved the quality of the measurements and residuals were again compared to the standards. RESULTS: After regression, 7 of the 9 the measurements were within, or close to (two times standard), standards. Error was caused by a combination of image quality issues associated with the laser scanner, as well as algorithmic issues associated with larger participants. CONCLUSIONS: Overall, the results are promising, and given the indicated population, a small number of minor improvements may very quickly allow the scanner to collect measurements on a clinical population.
Advances in neurology, 1997
The Neuroscientist, 1998
Objective: To present some recent developments and concepts emerging from both animal and human s... more Objective: To present some recent developments and concepts emerging from both animal and human studies aimed at enhancing recovery of walking after spinal cord injury (SCH. Data Sources: Researchers in the field of restoration of walking after SCI, as well as references extracted from searches in the Medline computerized database. Study Selection: Studies that reported outcome measures of walking for spinal cord injured persons with an incomplete motor function loss or cats with either a complete or incomplete spinal section. Data Extraction: Data were extracted and validity was assessed by the authors. Data Synthesis: This review shows that a multitude of interventions-mechanical, electrical, or pharmacologic-can increase the walking abilities of persons with SC1 who have incomplete motor function loss. Conclusions: A comprehensive evaluation of walking behavior requires tasks involving the different control variables. This comprehensive evaluation can be used to characterize the process of recovery of walking as well as the effectiveness of various treatments.
Archives of Physical Medicine and Rehabilitation, 1995
This report describes a treadmill apparatus for the evaluation and rehabilitation of gait in disa... more This report describes a treadmill apparatus for the evaluation and rehabilitation of gait in disabled persons. The apparatus incorporates a body weight support system as well as mechanisms to change certain conditions: treadmill belt speed, upward-downward and lateral slopes, and provision of obstacles. The apparatus enables elements of a treadmill walking pattern to be visible in persons for whom gait evaluation or rehabilitation may not otherwise be possible. It also allows for exploration of factors that limit the adaptability of gait in person after disease or injury by changing the mechanical demand of the locomotor task.
Archives of Physical Medicine and Rehabilitation, 1999
Objective: To present some recent developments and concepts emerging from both animal and human s... more Objective: To present some recent developments and concepts emerging from both animal and human studies aimed at enhancing recovery of walking after spinal cord injury (SCH. Data Sources: Researchers in the field of restoration of walking after SCI, as well as references extracted from searches in the Medline computerized database. Study Selection: Studies that reported outcome measures of walking for spinal cord injured persons with an incomplete motor function loss or cats with either a complete or incomplete spinal section. Data Extraction: Data were extracted and validity was assessed by the authors. Data Synthesis: This review shows that a multitude of interventions-mechanical, electrical, or pharmacologic-can increase the walking abilities of persons with SC1 who have incomplete motor function loss. Conclusions: A comprehensive evaluation of walking behavior requires tasks involving the different control variables. This comprehensive evaluation can be used to characterize the process of recovery of walking as well as the effectiveness of various treatments.
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Papers by Michel Ladouceur