Evaluation of maximal exercise performance, fatigue, and depression in athletes with acquired chronic training intolerance

Review of the scientific rationale, development and validation of the International Olympic Committee Relative Energy Deficiency in Sport Clinical Assessment Tool: V.2 (IOC REDs CAT2)-by a subgroup of the IOC consensus on REDs

Relative Energy Deficiency in Sport (REDs) has various different risk factors, numerous signs and symptoms and is heavily influenced by one's environment. Accordingly, there is no singular validated diagnostic test. This 2023 International Olympic Committee's REDs Clinical Assessment Tool-V.2 (IOC REDs CAT2) implements a three-step process of: (1) initial screening; (2) severity/risk stratification based on any identified REDs signs/symptoms (primary and secondary indicators) and (3) a physician-led final diagnosis and treatment plan developed with the athlete, coach and their entire health and performance team. The CAT2 also introduces a more clinically nuanced four-level traffic-light (green, yellow, orange and red) severity/risk stratification with associated sport participation guidelines. Various REDs primary and secondary indicators have been identified and 'weighted' in terms of scientific support, clinical severity/risk and methodological validity and usability, allowing for objective scoring of athletes based on the presence or absence of each indicator. Early draft versions of the CAT2 were developed with associated athlete-testing, feedback and refinement, followed by REDs expert validation via voting statements (ie, online questionnaire to assess agreement on each indicator). Physician and practitioner validity and usability assessments were also implemented. The aim of the IOC REDs CAT2 is to assist qualified clinical professionals in the early and accurate diagnosis of REDs, with an appropriate clinical severity and risk assessment, in order to protect athlete health and prevent prolonged and irreversible outcomes of REDs.

Ethnic differences in the consistency and accuracy of perceived exertion

OBJECTIVES

This study investigated the effect of weight loss and weight regain on accuracy of perceived exertion (APE) in previously overweight African American (AA) and European American (EA) women.

METHODS

Formerly overweight women (n = 102, age 20-44 years) completed a weight loss program to achieve BMI < 25 kg/m(2) . Physiological variable of exertion and rating of perceived exertion (RPE, Borg's 6-20 Scale) were recorded during submaximal aerobic exercise prior to, immediately following, and approximately 1 year after weight loss. APE was defined as the composite score of physiological variables (heart rate, ventilation rate, and respiratory exchange ratio) minus RPE.

RESULTS

APE was significantly different from the composite score of physiological variables at baseline and at 1-year follow-up for EA women (0.347 ± 0.88 P < 0.05 and 0.53 ± 0.92, P < 0.01, respectively) and at 1-year follow-up for AA (-0.37 ± 1.1, P < 0.01). EA women had lower physiological effort at baseline and 1-year follow-up states (-0.24 ± 0.66 P < 0.05; and, -0.27 ± 0.84 P < 0.05, respectively). AA women had higher physiological effort, at 1-year follow-up state (0.21 ± 0.61, P < 0.01).

CONCLUSIONS

Physiologic effort and perceived exertion contributed independently to the racial differences in APE, and APE may be an important trait to evaluate before planning an exercise intervention. Am. J. Hum. Biol. 28:398-404, 2016. © 2015 Wiley Periodicals, Inc.

Crawling to the finish line: why do endurance runners collapse? Implications for understanding of mechanisms underlying pacing and fatigue

Effective regulation of pace enables the majority of runners to complete competitive endurance events without mishap. However, some runners do experience exercise-induced collapse associated with postural hypotension, which in rare cases results from life-threatening conditions such as cardiac disorders, cerebral events, heat stroke and hyponatraemia. Despite the experience of either catastrophic system failure or extreme peripheral muscle fatigue, some runners persist in attempting to reach the finish line, and this often results in a sequence of dynamic changes in posture and gait that we have termed the 'Foster collapse positions'. The initial stage involves an unstable gait and the runner assumes the 'Early Foster' collapse position with hips slightly flexed and their head lowered. This unstable gait further degrades into a shuffle referred to as the 'Half Foster' collapse position characterized by hip flexion of approximately 90° with the trunk and head parallel to the ground. At this point, the muscles of postural support and the co-ordination of propulsion begin to be compromised. If the condition worsens, the runner will fall to the ground and assume the 'Full Foster' collapse position, which involves crawling forwards on knees and elbows towards the finish line, with their trunk angled such that the head is at a lower angle than the hips. Upon reaching the finish line, or sometimes before that, the runner may collapse and remain prone until recovering either with or without assistance or medical treatment. The Foster collapse positions are indicative of a final, likely primordial, protective mechanism designed to attenuate postural hypotension, cardiac 'pump' insufficiency or cerebral blood flow deficiency. Continuing to attempt to reach the finish line in this impaired state is also perhaps indicative of a high psychological drive or a variety of neurological and psychological pathologies such as diminished sensitivity to interoceptive feedback, unrealistic situational appraisal or extreme motivational drives. A better understanding of the physiological, neurological and psychological antecedents of the Foster collapse sequence remains an important issue with practical implications for runner safety and theoretical understanding of collapses during exercise.