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Home‐based exercise programs may offer a less costly alternative to providing exercise pre‐transplant to a large number of patients. We describe the changes in 6‐minute walk distance (6MWD) in lung transplant candidates who participated in a home‐based exercise program and their relationship to post‐transplant outcomes. Retrospectively, we investigated 159 individuals while awaiting transplantation who performed the surgery between 2011 and 2015. Primary outcome was 6MWD at time of assessment for transplant, last test prior to transplant and one‐month post‐transplant. 6MWD decreased by 28 ± 93.9 m between the time of assessment and the last 6MWD prior to transplantation (P < .001). Forty‐one patients (25.8%) increased their 6MWD (mean + 85.8 ± 42.8 m); 72 patients (45.3%) decreased their 6MWD (mean −109.8 ± 71.2 m); and 46 patients (28.9%) had no change in 6MWD (−1.5 ± 15.7 m). There was a moderate correlation (r = .528; P < .001) between the last 6MWD prior to transplant and 6MWD post‐transplant. Change in 6MWD prior to transplant weakly correlated with length of time on mechanical ventilation (r = −.185; P = .034). When adjusted for covariates, change in 6MWD prior to transplant was not associated with length of time on mechanical ventilation, total hospital LOS, or intensive care unit LOS. The majority of the patients were able to either increase or maintain their 6MWD while participating in a home‐based pre‐habilitation program during the waiting list period. Prospective research is needed to evaluate the effects of home‐based pre‐habilitation program for lung candidates.

Accurate prediction of the human response to ship motion can lead to improved safety and efficiency of ship operation and design. The objective of this thesis is to derive and validate a human postural stability model having similar dynamic response to an actual human when exposed to six-degree-of-freedom ship motion. The human body is modelled as a four-link inverted pendulum, which allows for representative motion of the ankles, knees, waist, and neck. Human postural stability experiments were performed during an eight day heavy-weather sea trial in the North Atlantic Ocean. This was the first known attempt to use a variety of advanced data acquisition techniques in a shipboard environment to record human sensory stimuli. This included using two full-body motion capture systems to record body segment positions and orientations, instrumented shoe insoles to measure somatosensory data, an inertial sensor to measure head vestibular data, and a head-mounted camera to capture visual proprioceptive data. The separate data sets were combined in order to describe the motion of each subject's centre of mass and centre of force within their base of support. Human postural reactions during the sea trial were correlated with the ship motion in order to derive control gains for the inverted pendulum model which included both open-loop and closed-loop components. Simulation results were compiled from 49 test cases and it was observed that the derived controller matched human response frequently in both postural roll and pitch. Further analysis indicated that there was a consistent relationship between the accuracy of the model's motions and the direction of greater ship angular motions. The specific contributions of this thesis include the spatial postural stability model, the detailed biometric data gathered during the sea trial, the control system developed by correlating ship motions with human response, and the compilation of comprehensive data sets of postural stability parameters of humans experiencing six-degree-of-freedom motion.ii Acknowledgements I would like to thank Rob Langlois, my supervisor and friend, for his support and guidance over the last five point five years of this doctorate degree. If you had not tempted me back to grad school with exciting research opportunities at a research facility that is even now still being built, none of this wonderful journey would have taken place.I would like to thank Aren Hunter, Roger Arsenault, Alex Ritchie, and the rest of the scientific staff at DRDC-Atlantic for all of their generous support in planning and performing the sea trial experiments. I would also like to extend my gratitude to the crew of CFAV Quest because without their help the human postural stability experiments would not have been as successful as they were.

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In naval engineering and related disciplines, it is common for dynamic models of the human body to be used in conjunction with quantitative records of body and ship motions, in order to study human balance behaviour while performing various shipboard activities. Research in this area can lead to improvements in ship operations and designs that improve crew safety and efficiency. This paper presents the development of a new spatial 18 degree-of-freedom (DOF)1 ship-inverted pendulum model that incorporates 6 DOF ship motion and 3 DOF joints representing ankle, knee, hip, and neck motions. The derived model is then validated by comparing it to similar models derived using alternative methods but simulated under equivalent input conditions.

Background. Measures of exercise capacity, frailty, and physical function are commonly used in lung transplant candidates and recipients to evaluate their physical limitations and the effects of exercise training and to select candidates for transplantation. It is unclear how these measures are related to clinical outcomes and healthcare utilization before and after lung transplantation. The purpose of this scoping review was to describe how measures of exercise capacity, physical function, and frailty are related to pre- and posttransplant outcomes. Methods. We considered studies of any design that included performance-based tests of exercise capacity, physical function, and frailty in adult lung transplant candidates or recipients. Outcomes of interest were clinical outcomes (eg, mortality, quality of life) and healthcare utilization. Results. Seventy-two articles met the inclusion criteria. The 6-min walk test (6MWT) was shown to be related to mortality on the waiting list with different distance values as cutoffs points. There were inconsistent results regarding the relationship of the 6MWT with other clinical outcomes. Few studies have examined the relationship between the cardiopulmonary exercise test or the short physical performance battery and clinical outcomes, although some studies have shown relationship with survival posttransplant and quality of life. Few studies examined the relationship between the tests of interest and healthcare utilization‚ and the results were inconsistent. Conclusions. Except for the relationship between the 6MWT and mortality on the waiting list, there is limited evidence regarding the relationship of performance-based measures of exercise capacity, frailty, and physical function with clinical outcomes or healthcare utilization.

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