Corrigendum: Fat oxidation rates and cardiorespiratory responses during exercise in different subject populations with post-acute sequelae of SARS-CoV-2 infection: a comparison with normative percentile values

[This corrects the article DOI: 10.3389/fphys.2023.1310319.].

Fat oxidation rates and cardiorespiratory responses during exercise in different subject populations with post-acute sequelae of SARS-CoV-2 infection: a comparison with normative percentile values

Introduction: Post-acute sequelae of SARS-CoV-2 infection (PASC) presents a spectrum of symptoms following acute COVID-19, with exercise intolerance being a prevalent manifestation likely linked to disrupted oxygen metabolism and mitochondrial function. This study aims to assess maximal fat oxidation (MFO) and exercise intensity at MFO (FATmax) in distinct PASC subject groups and compare these findings with normative data. Methods: Eight male subjects with PASC were involved in this study. The participants were divided into two groups: "endurance-trained" subjects (V ˙ O 2 max > 55 mL/min/kg) and "recreationally active" subjects (V ˙ O 2 max < 55 mL/min/kg). Each subject performed a graded exercise test until maximal oxygen consumption (V ˙ O 2 max ) to measure fat oxidation. Subsequently, MFO was assessed, and FATmax was calculated as the ratio between V ˙ O 2 at MFO and V ˙ O 2 max. Results: The MFO and FATmax of "endurance-trained" subjects were 0.85, 0.89, 0.71, and 0.42 and 68%, 69%, 64%, and 53%, respectively. Three out of four subjects showed both MFO and FATmax values placed over the 80th percentile of normative data. The MFO and FATmax of "recreationally active" subjects were 0.34, 0.27, 0.35, and 0.38 and 47%, 39%, 43%, and 41%, respectively. All MFO and FATmax values of those subjects placed below the 20th percentile or between the 20th and 40th percentile. Discussion: Significant differences in MFO and FATmax values between 'endurance-trained' and "recreationally active" subjects suggest that specific endurance training, rather than simply an active lifestyle, may provide protective effects against alterations in mitochondrial function during exercise in subjects with PASC.

"I Am on Top!": An Interactive Intervention Program to Promote Self-Regulation Processes in the Prevention of the Use of Doping in Sports High Schools

The use of substances to improve sports performance is a widespread phenomenon among adolescents. Several anti-doping programs have been developed, mainly based on knowledge-based evidence. The main aim of the present study was to implement an anti-doping intervention in sports high school students, based on a psychological framework, such as Socio-Cognitive Theory, through the development of a Serious Game (SG), i.e., digital learning based on the game. The experimental design included an intervention group (n = 167; F = 37.7%; Meanage = 17.5 years; SD = 0.58) and a control group (n = 112; F = 42%; Meanage = 17.6; SD = 1). Both of the groups completed the same questionnaire on two different occasions (i.e., time 1 and time 2) for measuring doping intention, self-regulatory efficacy to resist social pressure for the use of substances, moral disengagement, and doping knowledge. Data were analyzed through repeated measures of Group X Time ANOVA, demonstrating some degree of efficacy of the intervention, in particular in terms of the decrease in doping intention and the strengthening of doping knowledge. Moreover, the study demonstrated that the score obtained during the implementation of the SG could partially represent a coherent measure of the participants' beliefs regarding doping. These results could be considered a starting point for future research to better develop technological anti-doping interventions.

"I RUN CLEAN Project"-An Innovative and Self-Sustainable Approach to Develop Clean Sport Behaviours in Grassroots Athletes

The phenomenon of doping is a public health issue that poses threats to sport and society. In recent decades, the emphasis on efforts to address the issue and reduce the incidence of doping by young people in sport has shifted from deterrence through testing and punishment to the promotion of clean sport behaviours through values-based education. The "I Run Clean project" sought to develop new and effective tools targeting grassroots athletes and those around them (coaches, medical support personnel, sport leaders, parents). These included sport-specific e-learning and in-person peer-to-peer workshops led by trained volunteer ambassadors. The aim of all "I Run Clean" measures is to go beyond the warnings and provision of factual information about early anti-doping campaigns to a more holistic educational approach that focuses participants on their personal and sport-related values in order to encourage good decision-making and resistance to doping-related behaviours. This study evaluates the efficacy of the peer-to-peer workshops and their impact on selected psycho-social variables. The collaboration of the volunteer ambassadors is shown to effectively transmit the desired reasoning, reduce doping risk factors and enhance protective factors.

The Weekly Periodization of Top 5 Tour de France General Classification Finishers: A Multiple Case Study

PURPOSE

The aim of this study was to describe individual training characteristics, racing strategies, and periodization in preparation for the Tour de France in 2 world-class road cyclists finishing in the top 5 of the general classification.

METHODS

Week-by-week power meter training and racing data of 2 (A and B) road cyclists (age: 29 and 23 y; maximum oxygen consumption: 83 and 81 mL·min-1·kg-1; and relative 20-min record power output: 6.9 and 6.5 W·kg-1) in the preparation phase (December-July/August) leading up to the Tour de France were retrospectively analyzed. Weekly volume and intensity distribution in power zones were considered.

RESULTS

Cyclists A and B completed 46 and 19 races, 22.5 (6.3) and 18.2 (5.1) h·wk-1, with a pyramidal intensity distribution of 81.0%-13.3%-5.7%, and 88.8%-7.9%-3.3% in zone 1-zone 2-zone 3. Cyclist B spent 14 days at altitude. Increased high-intensity volume and polarization index occurred during race weeks. During periods without racing, training intensity progressively increased. Strength training was performed during November and December but not during the following months. During tapering, total exercise volume and time at high intensity decreased.

CONCLUSION

These data provide novel insights into the periodization of world-class road cyclists in advance of a top 5 placing in the Tour de France general classification.

How do world class top 5 Giro d'Italia finishers train? A qualitative multiple case study

The aim of this study was to describe individual training strategies in preparation to Giro d'Italia of three world class road cyclists who achieved a top 5 in the general classification. Day-to-day power meter training and racing data of three road cyclists (age: 26, 27, 25 years; relative maximum oxygen consumption: 81, 82, 80 ml·min^-1 ·kg^-1 ; relative 20-min record power output: 6.6, 6.6, 6.4 W kg^-1 ) of the 22 weeks (December-May) leading up to the top 5 in Giro d'Italia general classification were retrospectively analyzed. Weekly volume and intensity distribution were considered. Cyclists completed 17, 22, 29 races, trained averagely for 19.7 (7.9), 16.2 (7.0), 14.7 (6.2) hours per week, with a training intensity distribution of 91.3-6.5-2.2, 83.6-10.6-5.8, 86.7-8.9-4.4 in zone 1-zone 2-zone 3 before the Giro d'Italia. Two cyclists spent 55 and 39 days at altitude, one did not attend any altitude camp. Cyclists adopted an overall pyramidal intensity distribution with a relevant increase in high-intensity volume and polarization index in races weeks. Tapering phases seem to be dictated by race schedule instead of literature prescription, with no strength training performed by the three cyclists throughout the entire periodization.

Role of bone mineral density in predicting morphometric vertebral fractures in patients with HIV infection

This study investigated the bone of HIV patients both in terms of quantity and quality. It was found that HIV-infected patients did fracture independently of the degree of bone demineralization as in other forms of secondary osteoporosis.

INTRODUCTION

We aimed to determine the prevalence of vertebral fractures (VFs) in HIV patients who were screened by bone mineral density (BMD) and to explore possible factors associated with VFs.

METHODS

This is a cross-sectional study that included HIV-infected patients recruited in the Clinic of Infectious and Tropical Diseases and that underwent BMD measurement by dual-energy X-ray absorptiometry (DXA) at the lumbar spine and hip (Lunar Prodigy, GE Healthcare). For the assessment of VFs, anteroposterior and lateral X-ray examinations of the thoracic and lumbar spines were performed and were centrally digitized. Logistic regression models were used in the statistical analysis of factors associated with VFs.

RESULTS

One hundred thirty-one consecutive patients with HIV infection (93 M, 38 F, median age 51 years; range, 36-75) underwent BMD measurement: 25.2 % of patients showed normal BMD, while 45 % were osteopenic and 29.7 % osteoporotic. Prevalence of low BMD (osteopenia and osteoporosis) was higher in females as compared to males (90 vs 69 %) with no significant correlation with age and body mass index. VFs occurred more frequently in patients with low BMD as compared to patients with normal BMD (88.5 vs. 11.4 %; p < 0.001) without any significant difference between osteopenia and osteoporosis (43 vs. 46 %; p = 0.073). VFs were significantly associated with older age and previous AIDS events.

CONCLUSIONS

These results suggest a BMD <-1 threshold to identify patients at risk of skeletal fragility and, therefore, good candidates for morphometric evaluation of spine X-ray in line with other forms of secondary osteoporosis with impaired bone quality.