The role of exercise in aromatase inhibitor-induced arthralgia.

Aromatase inhibitors are prescribed in breast cancer due to their associated lower rate of cancer recurrence compared to tamoxifen. However, aromatase inhibitor-induced arthralgia (AIIA) is one of the leading causes of treatment nonadherence, increasing the risk of cancer recurrence. The pathophysiology of AIIA is poorly understood, and although current recommendations for AIIA include lifestyle changes and analgesics depending on the severity of symptoms, there is no established effective treatment. The aim of this study is to explore the presentation and mechanism of AIIA and investigate the feasibility and efficacy of different exercise interventions (aerobic, resistance, aerobic and resistance combined, and yoga or tai chi) in patients with AIIA to guide the development of formal exercise prescription guidelines. Findings indicate that a mixed-modality regimen of aerobic and resistance exercises is feasible and safe and may serve the most benefit in improving joint pain, functionality, and quality of life. More specifically, the weekly regimen should consist of 150 min of aerobic exercise with two sessions of at least six resistance exercises, 8 to 12 repetitions, three sets each. Supplementary yoga and tai chi may be recommended twice a week depending on a patient's target symptoms. Yoga was associated with improved physical functionality, whereas tai chi was related to improvements in mental health. However, the feasibility and impact of combined aerobic and resistance exercise protocols with yoga or tai chi in our target population were not investigated in this review. The use of large, randomized controlled trials is recommended for future studies.

Dual diagnosis of TBI and SCI: an epidemiological study in the pediatric population.

Introduction: Dual diagnosis (DD) with traumatic brain injury (TBI) and spinal cord injury (SCI) poses clinical and rehabilitation challenges. While comorbid TBI is common among adults with SCI, little is known about the epidemiology in the pediatric population. The primary objective of this study was to evaluate the prevalence of TBI among children in the United States hospitalized with SCI. Secondary objectives were to compare children hospitalized with DD with those with isolated SCI with regards to age, gender, race, hospital length of stay, and hospital charges. Methods: A retrospective analysis of hospital discharges among children aged 0-18 years occurring between 2016-2018 from U.S. hospitals participating in the Kids' Inpatient Database. ICD-10 codes were used to identify cases of SCI, which were then categorized by the presence or absence of comorbid TBI. Results: 38.8% of children hospitalized with SCI had a co-occurring TBI. While DD disproportionately occurred among male children (67% of cases), when compared with children with isolated SCI, those with DD were not significantly more likely to be male. They were more likely to be Caucasian. The mean age of children with DD (13.2 ± 5.6 years) was significantly less than that of children with isolated SCI (14.4 ± 4.3 years). DD was associated with longer average lengths of stay (6 versus 4 days) and increased mean total hospital charges ($124,198 versus $98,089) when compared to isolated SCI. Conclusion: Comorbid TBI is prevalent among U.S. children hospitalized with SCI. Future research is needed to better delineate the impact of DD on mortality, quality of life, and functional outcomes.

Acute Intermittent Porphyria: A Review and Rehabilitation Perspective.

Acute intermittent porphyria (AIP) is an uncommon metabolic disease that impacts multiple organs and can manifest in many ways. It is often misdiagnosed due to its nonspecific symptoms. Neurovisceral signs and symptoms should alert physicians to consider AIP in the differential after excluding more common causes. Identifying the underlying cause is critical in preventing acute attacks, and trigger avoidance is the optimal approach to managing AIP. Medications that are contraindicated should be reviewed thoroughly. Prompt intravenous hematin administration is the primary treatment for acute attacks, and additional pharmacological therapies may be necessary to treat concurrent symptoms. A severe neurological manifestation of AIP is flaccid paralysis or severe motor weakness, which can develop into total quadriplegia and respiratory insufficiency. A comprehensive rehabilitation program is an integral aspect of the treatment plan. Since the incidence of this disease is low, functional prognosis is not well-known. As a result, it is challenging to determine the most appropriate structure, intensity, and duration of rehabilitation therapy. By extending the treatment plan, individuals with tetraplegia due to AIP can continue to make functional gains years after the onset of weakness. Understanding the disease's functional prognosis will aid in coordinating resources and improving healthcare expenditures.

Interventional Spine Course: Improving Fluoroscopic Safety and Procedural Efficacy Among Physical Medicine and Rehabilitation Residents Using a Lecture and Model-Based Curriculum.

ABSTRACT: Therapeutic interventional techniques using fluoroscopy are often used in the management of spinal pain. Currently, there are no standardized means of instruction and assessment of fluoroscopic interventional spinal procedures for physiatry trainees. The aim of our study is to evaluate the utility of an interventional spine training course for physical medicine and rehabilitation residents in improving safety and efficacy when performing these procedures. We performed a prospective multiple cohort study analyzing interventional spine knowledge and procedural ability among physical medicine and rehabilitation residents after implementing a training course that used lectures, hands-on training, and video-recorded objective structured clinical examination self-assessments. Of the total of 28 physical medicine and rehabilitation residents over the 2-yr study period, each class saw a statistically significant improvement in mean objective structured clinical examination scores from pre-examination to postexamination ( P < 0.05). Written examination scores also had a statistically significant preimprovement to postimprovement in the postgraduate years 2 and 3 classes. Our study supports the use of an interventional spine course for physical medicine and rehabilitation residents, and by following the existing cohorts and adding more cohorts in the future, we will continue to demonstrate valuable and comprehensive results.

The effect of clinically elevated body mass index on physiological stress during manual lifting activities.

Individuals with a body mass index (BMI) classified as obesity constitute 27.7% of U.S. workers. These individuals are more likely to experience work-related injuries. However, ergonomists still design work tasks based on the general population and normal body weight. This is particularly true for manual lifting tasks and the calculation of recommended weight limits (RWL) as per National Institute of Occupational Safety & Health (NIOSH) guidelines. This study investigates the effects of BMI on indicators of physiological stress. It was hypothesized that, for clinically elevated BMI individuals, repeated manual lifting at RWL would produce physiological stress above safety limits. A repetitive box lifting task was designed to measure metabolic parameters: volume of carbon dioxide (VCO2) and oxygen (VO2), respiratory exchange ratio (RER), heart rate (HR), and energy expenditure rate (EER). A two-way ANOVA compared metabolic variables with BMI classification and gender, and linear regressions investigated BMI correlations. Results showed that BMI classification represented a significant effect for four parameters: VCO2 (p < 0.001), VO2 (p < 0.001), HR (p = 0.012), and EER (p < 0.001). In contrast, gender only had a significant effect on VO2 (p = 0.014) and EER (p = 0.017). Furthermore, significant positive relationships were found between BMI and VCO2 (R2 = 59.65%, p < 0.001), VO2 (R2 = 45.01%, p < 0.001), HR (R2 = 21.86%, p = 0.009), and EER (R2 = 50.83%, p < 0.001). Importantly, 80% of obese subjects exceeded the EER safety limit of 4.7 kcal/min indicated by NIOSH. Indicators of physiological stress are increased in clinically elevated BMI groups and appear capable of putting these individuals at increased risk for workplace injury.

The Effects of a Nutrition Education Program on Dietary Intake and Biomarkers in HIV+ Adults.

Background. People living with HIV (PLWH) have increased risk of cardiovascular disease (CVD). Dietary behavior modification may assist in the treatment of CVD, but the optimal dose of nutrition education is unknown. The current aim was to determine if a weekly 1-hour nutrition education program would improve multiple outcomes among PLWH. Methods. Participants (n = 62) were assessed on dietary intake, serum biomarkers, and physical characteristics at baseline and 3 months, and percent change was calculated. Participants were grouped into 3 attendance categories of the classes: none, fair, or good. Analyses of covariance were performed on the outcomes. Results. Calories, protein, fat, saturated fat, carbohydrate, sugar, added sugar, and glycemic load were significantly different (all P values <.05). Those who attended no class typically had increases in these variables versus those with fair or good attendance. High-density lipoprotein cholesterol (HDL-C; P = .006) and total cholesterol/HDL-C ratio (P = .083) were different, as those who attended no class or had fair attendance worsened, but those with good attendance improved. Conclusions. Several outcomes improved more so among those with good class attendance versus those with either fair or no attendance. Thus, an interactive nutrition education program may be an effective tool to help improve the health of PLWH.

Are Physical Fitness and CRP Related to Framingham Risk Score in HIV+ Adults?

Background. People living with HIV (PLWH) have increased risk of cardiovascular disease (CVD). The Framingham Risk Score (FRS) predicts a 10-year CVD risk. Its relationships to physical fitness and C-reactive protein (CRP) are not well established. The current aim is to determine the links between FRS, physical fitness, and CRP in PLWH. Methods. Participants (n = 87) were assessed on multiple biomarkers. The FRS was calculated with the respective variables. Other variables that correlated significantly with FRS were entered into a regression equation to determine their relationship to FRS. Results. The FRS for men was more than twice that for women (12.8 vs 6.0, P < .001). Men were more fit than women, but most participants were not fit. Aerobic capacity was predictive of FRS in men, but not in women, and muscular strength was not predictive of FRS. Women had more than double the CRP compared with men (7.9 vs 3.5 mg/L, P < .01), and it was unrelated to FRS. Conclusions. In men, aerobic capacity was significantly predictive of FRS, but muscular strength and CRP were unrelated to FRS in both genders. These results do not conclusively demonstrate that physical fitness and CRP are related to FRS in PLWH.

Energy expenditure and nutrient intake after spinal cord injury: a comprehensive review and practical recommendations.

Many persons with spinal cord injury (SCI) have one or more preventable chronic diseases related to excessive energetic intake and poor eating patterns. Appropriate nutrient consumption relative to need becomes a concern despite authoritative dietary recommendations from around the world. These recommendations were developed for the non-disabled population and do not account for the injury-induced changes in body composition, hypometabolic rate, hormonal dysregulation and nutrition status after SCI. Because evidence-based dietary reference intake values for SCI do not exist, ensuring appropriate consumption of macronutrient and micronutrients for their energy requirements becomes a challenge. In this compressive review, we briefly evaluate aspects of energy balance and appetite control relative to SCI. We report on the evidence regarding energy expenditure, nutrient intake and their relationship after SCI. We compare these data with several established nutritional guidelines from American Heart Association, Australian Dietary Guidelines, Dietary Guidelines for Americans, Institute of Medicine Dietary Reference Intake, Public Health England Government Dietary Recommendations, WHO Healthy Diet and the Paralyzed Veterans of America (PVA) Clinical Practice Guidelines. We also provide practical assessment and nutritional recommendations to facilitate a healthy dietary pattern after SCI. Because of a lack of strong SCI research, there are currently limited dietary recommendations outside of the PVA guidelines that capture the unique nutrient needs after SCI. Future multicentre clinical trials are needed to develop comprehensive, evidence-based dietary reference values specific for persons with SCI across the care continuum that rely on accurate, individual assessment of energy need.

Exercise to mitigate cardiometabolic disorders after spinal cord injury.

The cardiometabolic disorder (CMD) is a syndrome caused by coalescing of cardiovascular, endocrine, pro-thrombotic, and inflammatory health risks. Together, these risks confer a hazard as health-threatening as coronary artery disease or type2 diabetes, whether an individual has a diagnosis of coronary disease or diabetes, or not. CMD is most often defined by three or more of five clinically assessed risk components, notably obesity, insulin resistance, hypertension, hypertriglyceridemia, and depressed high-density lipoprotein cholesterol. Evidence currently suggests that worldwide CMD is expanding at a pandemic rate, and it is known that people living with spinal cord injuries (SCI) qualify for the diagnosis at more than 50% of the prevalence of a non-disabled cohort. A recent evidence-based guideline warned of the current state of CMD following SCI and recommended early lifestyle intervention incorporating exercise and prudent nutrition as a first-line disease countermeasure. This monograph will define the CMD following SCI, explore its underlying pathophysiology, and provide evidence that recommends exercise for CMD health hazards after SCI.

Comparison of Various Indices in Identifying Insulin Resistance and Diabetes in Chronic Spinal Cord Injury.

The purpose of this screening and diagnostic study was to examine the accord among indices of glucose metabolism, including the Homeostatic Model Assessment for Insulin Resistance (HOMA), HOMA2, Matsuda Index, Quantitative Insulin-sensitivity Check Index (QUICKI), hemoglobin A1C (HbA1C), and fasting plasma glucose (FPG) against intravenous glucose tolerance test-measured insulin sensitivity (Si) in individuals with chronic motor complete SCI. Persons with chronic (≥12-months post-injury) SCI (n = 29; 79% men; age 42.2 ± 11.4; body mass index 28.6 ± 6.4 kg/m2; C4-T10) were included. Measures were compared using adjusted R2 from linear regression models with Akaike information criterion (AIC, a measure of error). QUICKI had the greatest agreement with Si (adjusted R2 = 0.463, AIC = 91.1, p = 0.0001), followed by HOMA (adjusted R2 = 0.378, AIC = 95.4, p = 0.0008), HOMA2 (adjusted R2 = 0.256, AIC = 99.7, p = 0.0030), and the Matsuda Index (adjusted R2 = 0.356, AIC = 95.5, p = 0.0004). FPG (adjusted R2 = 0.056, AIC = 107.5, p = 0.1799) and HbA1C (adjusted R2 = 0.1, AIC = 106.1, p = 0.0975) had poor agreement with Si. While HbA1C and FPG are commonly used for evaluating disorders of glucose metabolism, QUICKI demonstrates the best accord with Si compared to the other measures.

Pathophysiology of Neurogenic Obesity After Spinal Cord Injury.

Individuals with a spinal cord injury (SCI) have a unique physiology characterized by sarcopenia, neurogenic osteoporosis, neurogenic anabolic deficiency, sympathetic dysfunction, and blunted satiety associated with their SCI, all of which alter energy balance and subsequently body composition. The distinct properties of "neurogenic obesity" place this population at great risk for metabolic dysfunction, including systemic inflammation, hyperglycemia, dyslipidemia, and hypertension. The purpose of this article is to demonstrate the relationship between neurogenic obesity and the metabolic syndrome after SCI, highlighting the mechanisms associated with adipose tissue pathology and those respective comorbidities. Additionally, representative studies of persons with SCI will be provided to elucidate the severity of the problem and to prompt greater vigilance among SCI specialists as well as primary care providers in order to better manage the epidemic from a public health perspective.

The Relationship between HIV Duration, Insulin Resistance and Diabetes Risk.

The risk of developing Type 2 Diabetes Mellitus in people living with HIV (PLWH) can be four times greater and can occur at an earlier age and even without the presence of obesity compared to those without HIV. Therefore, the purpose of this analytical cross-sectional study was to determine the relationship between HIV duration and glucose metabolism among PLWH. Eighty-two PLWH were categorized into shorter (≤15 years) or longer HIV duration (≥16 years) and then compared for differences in demographics, physical and clinical characteristics, biomarkers, and dietary intake. Compared to those with shorter HIV duration (n = 34), those with longer HIV duration (n = 48) were on average older (p = 0.02), reported lower consumption of alcohol (p = 0.05), had higher levels of homeostasis model assessment of insulin resistance (HOMA-IR, p = 0.02), were also more likely to be a woman (p = 0.06), and have higher levels of fasting insulin (p = 0.06). When adjusted for age and body weight, the levels of HOMA-IR and fasting insulin were higher (p = 0.02 and p = 0.04) with longer compared to shorter HIV duration, respectively. Longer exposure to HIV infection is associated with impaired insulin sensitivity. Continuing research aimed at the long-term effects of HIV infection and (antiretroviral therapy) is required.

RETRACTED ARTICLE: The Novel Effects of a Hydrolyzed Polysaccharide Dietary Supplement on Immune, Hepatic, and Renal Function in Adults with HIV in a Randomized, Double-Blind Placebo-Control Trial.

The primary objective of the study was to evaluate the effects of a hydrolyzed polysaccharide, rice bran arabinoxylan compound (RBAC), on immune, hepatic, and renal function in HIV + individuals. A six-month randomized double-blind placebo-controlled trial was utilized to conduct the intervention. Forty-seven HIV + participants on stable antiretroviral therapy were enrolled and randomly assigned to one of the two study conditions (n = 22 RBAC and n = 25 placebo) and consumed 3 gram/day of either compound for six months. Participants were assessed at baseline and 3 and 6 months follow-up for CD4+ and CD8+, liver enzymes, and kidney function. No side effects were reported, and liver and kidney markers nearly remained completely within normal limits. The percentage change in CD4+ was similar for the placebo (+2.2%) and RBAC (+3.1%) groups at 6 months follow-up. The percentage change in CD8+ count significantly decreased from baseline to 6 months in the RBAC group (-5.2%), whereas it increased in the placebo group (+57.8%; p = 0.04). The CD4+/CD8+ ratio improved clinically in the RBAC group from 0.95 (SD =0.62) at baseline to 1.07 (SD =0.11) at 6 months, whereas it declined in the placebo group from 0.96 (SD =0.80) at baseline to 0.72 (SD =0.59) at 6 months. Our results showed a statistically significant decrease in CD8+ count and a clinically significant increase in CD4+/CD8+ ratio for the RBAC group compared to the placebo group. Thus, the results of this study suggest that the immunomodulatory and antisenescent activities of RBAC are promising for the HIV population.

The effectiveness of a community-based exercise program on depression symptoms among people living with HIV.

HIV is a worldwide public health issue affecting millions of individuals, and people living with HIV (PLWH) are often affected by depression. Nonetheless, exercise can prevent and treat depression among PLWH. The aim of the present study was to investigate the effect of exercise on depression symptoms in PLWH. Using a prospective single-arm trial, a semi-supervised community-based exercise intervention was offered 3 times/week for 12 weeks to PLWH (n = 52; age: 49 ± 6 years; HIV diagnosis: 19 ± 15 years). Participants were divided into compliant (≥1 exercise session/week) and non-compliant (<1 exercise session/week) groups according to their attendance in the intervention. Depression symptoms were assessed using the Beck Depression Inventory (BDI), and the change in BDI from baseline to post-intervention was assessed with an analysis of covariance, adjusted for demographics. The post-intervention BDI score was significantly lower (p = 0.027) for the compliant group compared to the non-compliant group, and the rate of improvement from moderate/severe symptoms of depression to minimal symptoms of depression was four times greater in the compliant group. In conclusion, a community-based exercise program may be effective in reducing depression symptoms among PLWH.

Cardiovascular, endothelial function, and immune markers in response to treatment with a polysaccharide in HIV+ adults in a randomized, double-blind placebo-controlled trial.

BACKGROUND AND AIM: Given the ongoing problems of hypertension and endothelial dysfunction in the HIV population, the primary objective of the study was to assess the cardiovascular, endothelial function, and immune markers in response to rice bran arabinoxylan compound (RBAC) treatment in a sample of HIV+ adults on antiretroviral therapy (ART). STUDY DESIGN: A randomized, double-blind placebo-controlled trial of 6 months was used to execute the study. MATERIALS AND METHODS: Forty-seven subjects were enrolled and randomly assigned to one of two study conditions (n=22 RBAC and n=25 placebo) for 6 months with assessments at baseline and 3 and 6 months. A multivariate repeated measures analysis of variance model was used to assess the differences between RBAC and placebo groups in cardiovascular (systolic blood pressure), endothelial function (skin blood flow in response to nitric oxide), and immune (CD4+ cell count) markers from baseline to 6 months. RESULTS: The effect of treatment (RBAC versus placebo) was significant (Wilks' λ=0.92, F[3, 102]=3.07, P=0.03). The effect of time was significant (Wilks' λ=0.10, F[2, 103]=474.6, P<0.001). The overall interaction between treatment and time was significant (Wilks' λ=0.92, F[2, 103]=4.58, P=0.01). Time contrasts showed that a difference in the overall dependent variable did not occur from baseline to 3 months (F[1, 104]=2.7, P=0.10), marginally occurred from baseline to 6 months (F[1, 104]=3.2, P=0.08), and was significant from 3 to 6 months (F[1, 104]=6.43, P=0.01). CONCLUSIONS: The overall significant interaction suggests varying responses in the dependent variables between RBAC and placebo over time, which is being driven by systolic blood pressure, as it decreased in the RBAC group, but increased in the placebo group. In addition, CD4+ manifested a non-significant increase from baseline to 3 months then decreased from 3 to 6 months in the RBAC group, whereas it decreased at 3 months followed by a slight increase at 6 months in the placebo group. Skin blood flow in response to nitric oxide improved non-significantly overall in both groups, but worsened from 3 to 6 months in the placebo group. Thus, RBAC treatment may contribute to modest short-term improvements in systolic blood pressure, endothelial function, and CD4+ cell count, which could help improve the overall health profile of HIV+ adults. RELEVANCE FOR PATIENTS: Persons with HIV on ART suffer disproportionately from hypertension and endothelial dysfunction compared to the non-infected population, and conventional medical therapy does not alleviate these issues. RBAC is a safe, low-risk alternative that may help to improve the overall quality of life of these patients through modest improvements in these biomarkers plus CD4+ cell count.

Randomized Trial of Combined Aerobic, Resistance, and Cognitive Training to Improve Recovery From Stroke: Feasibility and Safety.

Background Physical exercise and cognitive training have been recommended to improve cognitive outcomes poststroke, but a multifaceted strategy including aerobic, resistance, and cognitive training to facilitate poststroke recovery has not been investigated. We aimed to assess the feasibility, adherence, and safety of a combined aerobic, resistance, and cognitive training intervention (CARET+CTI) after stroke. Methods and Results We prospectively randomized patients presenting with recent stroke to a comparison of a supervised 12-week CARET+CTI program and a control group receiving sham CARET+CTI. Participants were scheduled for 3 weekly CARET and CTI sessions. All participants underwent pre- and postintervention assessments of strength, endurance, and cognition. The primary outcomes were feasibility and adherence, defined as the ratio of scheduled and observed visits, and safety. We enrolled 131 participants, of whom 37 withdrew from the study. There were 17 (20%) withdrawals in the CARET+CTI and 20 (44%) in the control group. The observed-over-expected visit ratio was significantly higher in the intervention than in the control group (0.74±0.30 versus 0.54±0.38; P=0.003). A total of 99 adverse events were reported by 59 participants, none of which were serious and related to the intervention. Greater gains in physical, cognitive, and mood outcomes were found in the CARET+CTI group than in the control group, but were not statistically significant after adjustments. Conclusions A CARET+CTI intervention, after stroke, is safe, feasible, and has satisfactory participant adherence over 12 weeks. REGISTRATION URL: https://www.clini​caltr​ials.gov. Unique identifier: NCT02272426.

Corrigendum to "The Effect of a Hydrolyzed Polysaccharide Dietary Supplement on Biomarkers in Adults with Nonalcoholic Fatty Liver Disease".

[This corrects the article DOI: 10.1155/2018/1751583.].

The Novel Effects of a Hydrolyzed Polysaccharide Dietary Supplement on Immune, Hepatic, and Renal Function in Adults with HIV in a Randomized, Double-Blind, Placebo-Control Trial.

The primary objective of the study was to evaluate the effects of a hydrolyzed polysaccharide, rice bran arabinoxylan compound (RBAC), on immune, hepatic, and renal function in HIV + individuals. A 6-month randomized double-blind placebo-controlled trial was utilized to conduct the intervention. Forty-seven HIV + individuals on stable antiretroviral therapy were enrolled and randomly assigned to one of the 2 study conditions (n = 22 RBAC and n = 25 placebo) and consumed 3 gram/day of either compound for 6 months. Participants were assessed at baseline and 3 and 6 months follow-up for CD4+ and CD8+, liver enzymes, and kidney function. No side effects were reported, and liver and kidney markers remained nearly completely within normal limits. The percentage change in CD4+ was similar for the placebo (+2.2%) and RBAC (+3.1%) groups at 6 months follow-up. The percentage change in CD8+ count significantly decreased from baseline to 6 months in the RBAC group (-5.2%), whereas it increased in the placebo group (+57.8%; p = 0.04). The CD4+/CD8+ ratio improved clinically in the RBAC group from 0.95 (SD = 0.62) at baseline to 1.07 (SD = 0.11) at 6 months, whereas it declined in the placebo group from 0.96 (SD = 0.80) at baseline to 0.72 (SD = 0.59) at 6 months. Our results showed a statistically significant decrease in CD8+ count and a clinically significant increase in CD4+/CD8+ ratio for the RBAC group compared to the placebo group. Thus, the results of this study suggest that the immunomodulatory and antisenescent activities of RBAC are promising for the HIV population.

Celebrating 40 Years of Ironman: How the Champions Perform.

We aimed to determine which discipline had the greater performance improvements in the history of Ironman triathlon in Hawaii and also which discipline had the greater influence in overall race time. Data from 1983 to 2018 of the top three women and men of each year who competed in the Ironman World Championship were included. In addition to exploratory data analyses, linear regressions between split times and years of achievement were performed. Further, a stepwise multiple linear regression was applied using total race time as the dependent variable and split times as the independent variables. Both women and men significantly improved their performances from 1983 to 2018 in the Ironman World Championship. Swimming had the largest difference in improvements between men and women (3.0% versus 12.1%, respectively). A negative and significant decrease in each discipline was identified for both women and men, with cycling being the discipline with the greatest reduction. The results from the stepwise multiple regression indicated that cycling was the discipline with the highest influence on overall race time for both sexes. Based on the findings of this study, cycling seems to be the Ironman triathlon discipline that most improved overall race times and is also the discipline with the greatest influence on the overall race time of elite men and women in the Ironman World Championship.

Cycling as the Best Sub-8-Hour Performance Predictor in Full Distance Triathlon.

For any triathlon distance (short, Olympic, half-distance and full-distance), competitors spend more time cycling than swimming or running, but running has emerged as the discipline with the greatest influence on overall performance at the Olympic distance. However, there is a lack of evidence on which discipline has the greatest influence on performance in the overall full-distance triathlon (3.8 km swimming/180 km cycling/42.195 km running), especially for the fastest performing athletes of all time. The total race times of 51 fastest triathletes (sub-8-hour) were studied, while for the split times, a sample of 44 participants was considered. The discipline that seemed to better predict total race time was cycling (coefficient = 0.828; p < 0.001), followed by running (coefficient = 0.726; p < 0.001) and swimming (coefficient = 0.476; p < 0.001). Furthermore, cycling was the discipline with the highest performance improvement over the years, whereas running had a slightly decrease. In conclusion, cycling seems to be the discipline with greater influence in final result for the full-distance triathlon.