ECSS Paris 2023: OP-MH39
INTRODUCTION: A common symptom management strategy in long COVID is energy management [1]. Energy management is used to help people manage their ‘energy envelope’ to limit incidence of post-exertional malaise (PEM) [2]. However, a platform that warns participants of potential PEM, informed by granular biofeedback, using validated instruments, was non-existent to date. Therefore, the aim of this trial was to determine if activity tracking combined with just-in-time messages helped people with long COVID reduce PEM over six months. We hypothesised a priori that a just-in-time intervention to assist energy management (intervention group) would reduce PEM compared to usual care (control). METHODS: Following ethical approval, and informed consent, 250 participants were randomised 1:1 into intervention or control. All participants downloaded the study app (“Pace Me”), while only the intervention were provided with an activity tracker (Fitbit Charge 5, Fitbit Inc., San Francisco, CA, USA) and downloaded the FitBit app. The intervention version of the app included energy management support and data collection instruments, whilst the control version included only data collection. Intervention group participants had a personalised daily activity allowance, initially set to <30 minutes of activity >60% of their age-predicted heart rate maximum and received notifications if they exceeded 50%, 75%, and 100% of their allowance. Notifications included an alert message and support tips. The primary outcome was PEM assessed using the DePaul Symptom Questionnaire - PEM (DSQ-PEM) [3], pre- and post-intervention. RESULTS: The DSQ-PEM sum of the intervention group was 48 (95% CI 44-53) at baseline and 46 (95% CI 41-51) post-intervention. The control group value was 47 (95% CI 42-52) at baseline and 44 (95% CI 39-49) at follow-up (interaction effect p=.614, η²p=.002; trivial). Additionally, the number of individuals classified as positive for PEM (i.e. discrete yes/no) decreased from baseline to follow-up (p=.004). There were 118 participants with no change, 31 who improved, and 12 who worsened. No between-group effects were observed at baseline (p=.411) or follow-up (p=.155). CONCLUSION: A just-in-time intervention using a wearable activity tracker was no more effective than control at reducing PEM in people with long COVID. A regression to the mean may have occurred, whereby people with long COVID recovered naturally, and this is supported by our categorical analysis observing several people went from PEM positive to PEM negative over six months. REFERENCES 1 NICE. Myalgic encephalomyelitis (or encephalopathy)/chronic fatigue syndrome: diagnosis and management. chronic fatigue syndrome. 2021;87. 2 Goudsmit et al. Disabil Rehabil. 2012;34:1140–7. doi: 10.3109/09638288.2011.635746 3 Cotler J et al. Diagnostics. 2018;8:66. doi: 10.3390/diagnostics8030066
Read CV Lawrence HayesECSS Paris 2023: OP-MH39
INTRODUCTION: Previous research from our group developed a regression equation to estimate the oxygen cost (V̇O₂) of walking at a range of velocities collected at 1 min increments on a treadmill in healthy adult participants whilst wearing a foot-pod accelerometer (StrydPower)1. This represents typical validation of wearable technology but is it applicable for older clinical populations? We aimed to compare estimated V̇O₂ from the StrydPower watts with actual V̇O₂ while patients performed their prescribed moderate intensity walking paces. METHODS: During the prescribed moderate aerobic walking component on an indoor track of a routine cardiac rehabilitation session, patients wore a portable pulmonary gas-exchange monitor and a StrydPower. Along with the continuous gas exchange variables, walking watts, heart rate, and ratings of perceived exertion were also collected continuously for a minimum of 10 mins. Mean data for the last two minutes of the walking were analysed. Analysis of agreement between actual V̇O₂ and that estimated from our existing StrydPower watts/V̇O₂ regression equation, included a T-test, intra-class-correlation coefficient (ICC) and bias +/-95 Limits of Agreement (LoA). RESULTS: Seventeen participants completed the study (7 female, 67.1 +/-14.9 years). The difference in actual vs estimated V̇O2 was clinically small but significant, (16.7 +/-3.3 and 14.5+/-3.2 ml·kg-1·mins-1; p = .003). The related ICC was moderate and significant (r = .53, p = .01) and the bias +/- 95%LoA was 2.2 +/- 5.0 ml·kg-1·mins. CONCLUSION: The use of a StrydPower foot pod accelerometer to estimate the oxygen cost of moderate intensity walking in a group of cardiac rehabilitation participants showed a moderate agreement for clinical significance. However, its validity stills needs further specific precision and evaluation for older clinical populations in relation to two factors typically questioned when using commercial wearable technologies; i. the criterion data from which V̇O₂ estimates were derived were healthy young adults and ii. The criterion data were measured on a treadmill collected at 1 min intervals as opposed to longer duration steady state. Taking these factors into account shows encouraging applications for remote monitoring of walking intensity with the StrydPower in cardiac populations. 1Jones, S., Burt, D., Pheasey, C., Buckley, J (2024) ECSS Glasgow 2024: 29th Annual Congress of the European College of Sport Science, 2-5 July 2024, Glasgow, Scotland, UK ; book of abstracts. European College of Sport Science.
Read CV Sam JonesECSS Paris 2023: OP-MH39
INTRODUCTION: The interaction of a runner with footwear from the early familiarization period to long-term wear are still not fully understood. Shoe characteristics such as foam type and hardness may play key roles in the interplay between athlete and footwear during familiarization and long-term use. This study assessed how running economy, gait and perceived comfort evolved when runners used two identical shoes differing only in the hardness of the midsole foam. METHODS: Fourteen healthy males (age: 30 ± 4 years, weight: 73 ± 6 kg, height: 181 ± 3 cm, V̇O2peak: 56.0 ± 16.9 ml∙kg-1∙min-1) took part in this longitudinal study. Participants were given a pair of soft (SS, Shore C Hardness 45, energy return [ER] 6.4 J) and hard (HS, Shore C Hardness 70, ER 5.7 J) shoes to alternate in use during training. They visited the laboratory for assessments of running economy, spatiotemporal and perceptual variables at four different points of shoe mileage (0 km, 30–50 km, 150–200 km and 250-300 km, the latter performed by n = 8 participants). Tests consisted of three 5-min runs in each shoe condition with 2-min break inbetween, in randomized, balanced order, while assessing gas exchange, spatiotemporal, and perceptual variables. At the last visit, both pairs of old shoes were randomly rotated with a new pair of shoes. RESULTS: In the SS, V̇O₂ was 1.4–2.3% lower than in the HS across all visits (all p < 0.03) while no longitudinal changes were observed and no difference observed between old and new shoes in the last visit. HR was 1.2–2.1 bpm lower in the SS compared with the HS at visits 1 and 2 (both p < 0.02), with no detectable differences thereafter. The SS was also associated with greater comfort, with 17-26 points higher (0–100 VAS scale) than the HS, across all visits (all p < 0.04). From visit 1 to 3, HR decreased in both the SS (-6.3 ± 2.2 bpm; p = 0.01) and the HS (-6.9 ± 2.5 bpm; p = 0.02). Comfort decreased across the first 3 visits in the HS only while remaining unchanged in the SS. Changes in gait variables were minimal between shoe conditions and over time. CONCLUSION: The softer foam improved running economy and perceived comfort during the entire distance of 300 km with no visible divergent effects of shoe degradation over this mileage, and with only minimal changes in spatiotemporal variables. Since no noticeable detrimental effects of footwear wear were detected up to 300 km with both soft and hard shoe models, the footwear can be considered reliable for competition and testing up to this distance. Potential benefits of footwear familiarization were either not present or were quickly cancelled out by very early foam degradation. As physiological variables remained stable up to 300 km of wear while comfort decreased substantially for the HS model, perceived comfort seems to play no role in modulating running economy.
Read CV Elisa CedroECSS Paris 2023: OP-MH39