Transitioning to Minimal Footwear: a Systematic Review of Methods and Future Clinical Recommendations

Recent interest in barefoot running has led to the development of minimalist running shoes that are popular in distance runners. A careful transition to these shoes has been suggested and examined in the literature. However, no guidelines based on systematic evidence have been presented

Transitioning to minimal running footwear; implications for performance and running related injury when compared to conventional running shoes.

AIM: To investigate any changes in running economy or factors related to injury before and after a minimalist footwear (MFW) transition with gait-retraining when compared with conventional running shoes (CRS). INTRODUCTION: Recent interest in barefoot running has resulted in the development of a new footwear type which incorporates minimal cushioning and structural properties, in contrast with CRS. These MFW have been suggested to influence running kinetics and kinematics and may have a positive impact on performance and injury risk. However there is currently a dearth of scientific evidence available to support this theory. Of the limited research available the vast majority has only used acute comparisons between CRS and MFW, and has not considered the effect of “transitioning” into MFW over a period of time, with or without “barefoot” gait-retraining. METHODS: In all studies, effects for time (pre to post intervention), and condition (MFW vs. CRS) were evaluated, where participants were required to familiarise with MFW during the intervention. Study one examined changes in running economy (RE) with no feedback or gait-retraining, in contrast study two examined RE with deliberate gait-retraining included to the MFW transition. Study three investigated changes to plantar pressures and forces. Finally, study four evaluated kinetics and kinematics associated with injury. RESULTS: Following a MFW intervention, RE was found to improve 8.09% in MFW but not in CRS. However, when gait-retraining was included, no significant change in RE was observed over time. RE was significantly better in MFW compared to CRS irrespective of time (approx. 2.9% better in MFW). A MFW transition with gait-retraining was found to reduce plantar forces by 17.6%, loading rate by 33%, and the impact peak by 9%, which was not observed to the same degree in CRS. However, significantly higher plantar pressures and loading rates were observed in MFW when directly compared to CRS throughout testing. CONCLUSION: A MFW transition was found to significantly improve RE when gait-retraining was not included. However, gait-retraining may have a negative influence on RE. MFW and gait-retraining reduced impact variables over time. In addition, there was a reduction in plantar pressures under the heel, and no significant increase in pressures in the forefoot as a result of the intervention. With respect to condition, RE was better in MFW, but higher plantar pressures and loading rates were noted in MFW vs. CRS that may increase injury risk during this transition period

Proposal of a Selection Protocol for Replication of Studies in Sports and Exercise Science

To improve the rigor of science, experimental evidence for scientific claims ideally needs to be replicated repeatedly with comparable analyses and new data to increase the collective confidence in the veracity of those claims. Large replication projects in psychology and cancer biology have evaluated the replicability of their fields but no collaborative effort has been undertaken in sports and exercise science. We propose to undertake such an effort here. As this is the first large replication project in this field, there is no agreed-upon protocol for selecting studies to replicate. Criticism of previous selection protocols include claims they were non-randomised and non-representative. Any selection protocol in sports and exercise science must be representative to provide an accurate estimate of replicability of the field. Our aim is to produce a protocol for selecting studies to replicate for inclusion in a large replication project in sports and exercise science

Kinetic changes during a six-week minimal footwear and gait-retraining intervention in runners.

An evaluation of a six-week Combined minimal footwear transition and gait-retraining combination vs. gait retraining only on impact characteristics and leg stiffness. Twenty-four trained male runners were randomly assigned to either (1) Minimalist footwear transition Combined with gait-retraining over a six-week period ("Combined" group; n = 12) examined in both footwear, or (2) a gait-retraining group only with no minimalist footwear exposure ("Control"; n = 12). Participants were assessed for loading rate, impact peak, vertical, knee and ankle stiffness, and foot-strike using 3D and kinetic analysis. Loading rate was significantly higher in the Combined group in minimal shoes in pre-tests compared to a Control (P ≤ 0.001), reduced significantly in the Combined group over time (P ≤ 0.001), and was not different to the Control group in post-tests (P = 0.16). The impact peak (P = 0.056) and ankle stiffness reduced in both groups (P = 0.006). Loading rate and vertical stiffness was higher in minimalist footwear than conventional running shoes both pre (P ≤ 0.001) and post (P = 0.046) the intervention. There has a higher tendency to non-rearfoot strike in both interventions, but more acute changes in the minimalist footwear. A Combined intervention can potentially reduce impact variables. However, higher loading rate initially in minimalist footwear may increase the risk of injury in this condition

Screening of healthcare workers for SARS-CoV-2 highlights the role of asymptomatic carriage in COVID-19 transmission

Funder: Addenbrooke's Charitable Trust, Cambridge University Hospitals; FundRef: http://dx.doi.org/10.13039/501100002927Significant differences exist in the availability of healthcare worker (HCW) SARS-CoV-2 testing between countries, and existing programmes focus on screening symptomatic rather than asymptomatic staff. Over a 3 week period (April 2020), 1032 asymptomatic HCWs were screened for SARS-CoV-2 in a large UK teaching hospital. Symptomatic staff and symptomatic household contacts were additionally tested. Real-time RT-PCR was used to detect viral RNA from a throat+nose self-swab. 3% of HCWs in the asymptomatic screening group tested positive for SARS-CoV-2. 17/30 (57%) were truly asymptomatic/pauci-symptomatic. 12/30 (40%) had experienced symptoms compatible with coronavirus disease 2019 (COVID-19)>7 days prior to testing, most self-isolating, returning well. Clusters of HCW infection were discovered on two independent wards. Viral genome sequencing showed that the majority of HCWs had the dominant lineage B∙1. Our data demonstrates the utility of comprehensive screening of HCWs with minimal or no symptoms. This approach will be critical for protecting patients and hospital staff

SARS-CoV-2 Omicron is an immune escape variant with an altered cell entry pathway

Vaccines based on the spike protein of SARS-CoV-2 are a cornerstone of the public health response to COVID-19. The emergence of hypermutated, increasingly transmissible variants of concern (VOCs) threaten this strategy. Omicron (B.1.1.529), the fifth VOC to be described, harbours multiple amino acid mutations in spike, half of which lie within the receptor-binding domain. Here we demonstrate substantial evasion of neutralization by Omicron BA.1 and BA.2 variants in vitro using sera from individuals vaccinated with ChAdOx1, BNT162b2 and mRNA-1273. These data were mirrored by a substantial reduction in real-world vaccine effectiveness that was partially restored by booster vaccination. The Omicron variants BA.1 and BA.2 did not induce cell syncytia in vitro and favoured a TMPRSS2-independent endosomal entry pathway, these phenotypes mapping to distinct regions of the spike protein. Impaired cell fusion was determined by the receptor-binding domain, while endosomal entry mapped to the S2 domain. Such marked changes in antigenicity and replicative biology may underlie the rapid global spread and altered pathogenicity of the Omicron variant

Training and technique choices predict self-reported running injuries: an international study

Objectives: The aim of this study was to describe the self-reported injury, training, and running technique choices of regular runners in four international regions. Design and setting: 756 participants began an expert derived self-report online survey in Ireland, USA, Hong Kong and Australia. Participants: 325 participants completed the survey (age = 38 ± 10 years; weight = 68.0 ± 13.1 kg; height = 1.70 ± 0.10 m). Main outcome measures: Descriptive statistics are reported examining injury incidence and location; shoe and orthosis choices; and training and technique practices. A backwards logistic regression was implemented to examine associations between injury and training choices. Results: 68.3% reported having an injury in the last year. 81.45% of these injuries were believed to be running related. A large variation in training and footwear choices were observed for respondents. The regression (P ≤ 0.001) explained 20% of the variance in injury selection (Nagelkerke R2) and was able to identify 73% of cases accurately. Associated injury factors included competitive running, running on more than one surface, younger age, having a lower running age, and a higher proportion of running at an easy intensity. Conclusions: The high amount of variability in runner's choices highlights the lack of consistent information being presented to them and may be the reason for the high injury incidence

The nature of our literature

Scientists rely upon an accurate scientific literature in order to build and test new theories about the natural world. In the past decade, observational studies of the scientific literature have indicated that numerous questionable research practices and poor reporting practices may be hindering scientific progress. In particular, 3 recent studies have indicated an implausibly high rate of studies with positive (i.e., hypothesis confirming) results. In sports medicine, a field closely related to kinesiology, studies that tested a hypothesis indicated support for their primary hypothesis ~70% of the time. However, a study of journals that cover the entire field of kinesiology has yet to be completed, and the quality of other reporting practices, such as clinical trial registration, has not been evaluated. In this study we retrospectively evaluated 300 original research articles from the flagship journals of North America (Medicine and Science in Sports and Exercise), Europe (European Journal of Sport Science), and Australia (Journal of Science and Medicine in Sport). The hypothesis testing rate (~64%) and positive result rate (~81%) were much lower than what has been reported in other fields (e.g., psychology), and there was only weak evidence for our hypothesis that the positive result rate exceeded 80%. However, the positive result rate is still considered unreasonably high. Additionally, most studies did not report trial registration, and rarely included accessible data indicating rather poor reporting practices. The majority of studies relied upon significance testing (~92%), but it was more concerning that a majority of studies (~82%) without a stated hypothesis still relied upon significance testing. Overall, the positive result rate in kinesiology is unacceptably high, despite being lower than other fields such as psychology, and most published manuscripts demonstrated subpar reporting practices

Malaria after international travel: A GeoSentinel analysis, 2003-2016

BACKGROUND: More than 30,000 malaria cases are reported annually among international travellers. Despite improvements in malaria control, malaria continues to threaten travellers due to inaccurate perception of risk and sub-optimal pre-travel preparation. METHODS: Records with a confirmed malaria diagnosis after travel from January 2003 to July 2016 were obtained from GeoSentinel, a global surveillance network of travel and tropical medicine providers that monitors travel-related morbidity. Records were excluded if exposure country was missing or unascertainable or if there was a concomitant acute diagnosis unrelated to malaria. Records were analyzed to describe the demographic and clinical characteristics of international travellers with malaria. RESULTS: There were 5689 travellers included; 325 were children <18 years. More than half (53%) were visiting friends and relatives (VFRs). Most (83%) were exposed in sub-Saharan Africa. The median trip duration was 32 days (interquartile range 20-75); 53% did not have a pre-travel visit. More than half (62%) were hospitalized; children were hospitalized more frequently than adults (73 and 62%, respectively). Ninety-two per cent had a single Plasmodium species diagnosis, most frequently Plasmodium falciparum (4011; 76%). Travellers with P. falciparum were most frequently VFRs (60%). More than 40% of travellers with a trip duration ≤7 days had Plasmodium vivax. There were 444 (8%) travellers with severe malaria; 31 children had severe malaria. Twelve travellers died. CONCLUSION: Malaria remains a serious threat to international travellers. Efforts must focus on preventive strategies aimed on children and VFRs, and chemoprophylaxis access and preventive measure adherence should be emphasized