Using an Ingestible Telemetric Temperature Pill to Assess Gastrointestinal Temperature During Exercise.

Exercise results in an increase in core body temperature (Tc), which may reduce exercise performance and eventually can lead to the development of heat-related disorders. Therefore, accurate measurement of Tc during exercise is of great importance, especially in athletes who have to perform in challenging ambient conditions. In the current literature a number of methods have been described to measure the Tc (esophageal, external tympanic membrane, mouth or rectum). However, these methods are suboptimal to measure Tc during exercise since they are invasive, have a slow response or are influenced by environmental conditions. Studies described the use of an ingestible telemetric temperature pill as a reliable and valid method to assess gastrointestinal temperature (Tgi), which is a representative measurement of Tc. Therefore, the goal of this study was to provide a detailed description of the measurement of Tgi using an ingestible telemetric temperature pill. This study addresses important methodological factors that must be taken into account for an accurate measurement. It is recommended to read the instructions carefully in order to ensure that the ingestible telemetric temperature pill is a reliable method to assess Tgi at rest and during exercise

The binding study advice in medical education: a 2-year experience.

To improve the effectiveness of higher education, Dutch universities implemented the binding study advice at medical faculties. Accordingly, medicine students of Radboud University need to gain ≥ 42 out of 60 European Credit Transfer System (ECTS) credits to obtain a positive binding study advice and to continue their study programme. In case of a negative advice, the student is obliged to terminate the study, and he/she cannot register for the same study programme in the Netherlands within the next three years. The purpose of this manuscript is to evaluate the effect of implementation of the binding study advice on study outcomes. First, the binding study advice did not impact on student performance, as the average ECTS credits were comparable before and after its introduction. Second, study progress improved 8 % with 93 % of the students obtaining access to the second year of the study programme after binding study advice implementation. Third, the binding study advice did not impact propaedeutic graduation rates. These data demonstrate that the implementation of the binding study advice in medical faculties has only a small impact on study outcomes. The high performance levels of medical students compared with peers at other faculties are likely to contribute to these findings and suggest a 'ceiling effect' in the potential improvement of study outcomes at medical faculties

Benefits of lifelong exercise training on left ventricular function after myocardial infarction.

Background Endurance exercise training induces cardio-protective effects, but athletes are not exempted from a myocardial infarction. Evidence from animal studies suggests that exercise training attenuates pathological left ventricular remodelling following myocardial infarction. We tested the hypothesis that lifelong exercise training is related to attenuated pathological left ventricular remodelling after myocardial infarction as evidenced by better left ventricular systolic function in veteran athletes compared to sedentary peers. Design This was a cross-sectional study. Methods Sixty-five males (60 ± 6 years) were included and allocated to four groups based on lifelong exercise training volumes: (a) athletes ( n = 18), (b) post-myocardial infarction athletes (athletes + myocardial infarction, n = 20), (c) sedentary controls ( n = 13), and (d) post-myocardial infarction controls (sedentary controls + myocardial infarction, n = 14). Athletes were lifelong (≥20 years) highly physically active (≥30 metabolic equivalent of task (MET)-h/week), whereas sedentary controls did not meet the exercise guidelines (<10 MET-h/week) for the past 20 years. left ventricular systolic function, diastolic function and wall strain were measured using echocardiography. Results Cardiac enzyme markers (creatine-kinase, creatinine, aspartate transaminase and lactate dehydrogenase) following myocardial infarction and infarct location did not differ between athletes + myocardial infarction and sedentary controls + myocardial infarction. Left ventricular ejection fraction was significantly higher in athletes (61% ± 4), athletes + myocardial infarction (58% ± 4) and sedentary controls (57% ± 6) compared to sedentary controls + myocardial infarction (51% ± 7; p < 0.01). Left ventricular circumferential strain was superior in athletes (-19% (-21% to -17%), athletes + myocardial infarction (-16% (-20% to -12%)), and sedentary controls (-15% (-18% to -14%) compared to sedentary controls + myocardial infarction (-13% (-15% to -8%), p < 0.01). Diastolic function parameters did not differ across groups. Conclusion These findings suggest that lifelong exercise training may preserve left ventricular systolic function and possibly attenuates or minimises the deleterious effects of pathological post-myocardial infarction left ventricular remodelling in veteran athletes

The impact of exercise-induced core body temperature elevations on coagulation responses.

OBJECTIVES: Exercise induces changes in haemostatic parameters and core body temperature (CBT). We aimed to assess whether exercise-induced elevations in CBT induce pro-thrombotic changes in a dose-dependent manner. DESIGN: Observational study. METHODS: CBT and haemostatic responses were measured in 62 participants of a 15-km road race at baseline and immediately after finishing. As haemostasis assays are routinely performed at 37°C, we corrected the assay temperature for the individual's actual CBT at baseline and finish in a subgroup of n=25. RESULTS: All subjects (44±11 years, 69% male) completed the race at a speed of 12.1±1.8km/h. CBT increased significantly from 37.6±0.4°C to 39.4±0.8°C (p<0.001). Post-exercise, haemostatic activity was increased, as expressed by accelerated thrombin generation and an attenuated plasmin response. Synchronizing assay temperature to the subjects' actual CBT resulted in additional differences and stronger acceleration of thrombin generation parameters. CONCLUSIONS: This study demonstrates that exercise induces a prothrombotic state, which might be partially dependent on the magnitude of the exercise-induced CBT rise. Synchronizing the assay temperature to approximate the subject's CBT is essential to obtain more accurate insight in the haemostatic balance during thermoregulatory challenging situations. Finally, this study shows that short-lasting exposure to a CBT of 41.2°C does not result in clinical symptoms of severe coagulation. We therefore hypothesize that prolonged exposure to a high CBT or an individual-specific CBT threshold needs to be exceeded before derailment of the haemostatic balance occurs

Time-course of vascular adaptations during 8 weeks of exercise training in subjects with type 2 diabetes and middle-aged controls

CONCLUSION: Training leads to rapid improvement in brachial artery vascular function in diabetes patients and controls. In contrast to previous observations in healthy young subjects, the increase in function was preserved after 8 weeks of training in middle-aged diabetes patients and controls, suggesting a different time-course in vascular adaptations in subjects with endothelial dysfunction

Altered core and skin temperature responses to endurance exercise in heart failure patients and healthy controls.

BACKGROUND: Exercise training represents a central aspect of rehabilitation of heart failure patients. Previous work on passive heating suggests impaired thermoregulatory responses in heart failure patients. However, no previous study directly examined thermoregulatory responses to an exercise bout, that is, active heating, as typically applied in rehabilitation settings in heart failure. DESIGN: Cross-sectional observational study to compare changes in core body temperature (Tcore) and skin temperature (Tskin) during exercise between heart failure patients and controls. METHODS: Fourteen heart failure subjects (65 ± 7 years, 13:1 male:female) and 14 healthy controls (61 ± 5 years, 12:2 male:female) were included. Tcore (telemetric temperature pill) and Tskin (skin thermistors) were measured continuously during a 45-min cycle exercise at comparable relative exercise intensity. RESULTS: Tcore increased to a similar extent in both groups (controls 1.1 ± 0.4℃, heart failure patients 0.9 ± 0.3℃, 'time*group': p = 0.15). Tskin decreased during the initial phase of exercise in both groups, followed by an increase in Tskin in controls (1.2 ± 1.0℃), whilst Tskin remained low in HF patients (-0.3 ± 1.4℃) ('time*group': p  0.05). CONCLUSION: Heart failure patients and controls show comparable exercise-induced increase in Tcore, whilst heart failure patients demonstrate altered Tskin responses to exercise and attenuated elevation in Tskin per increase in Tcore. These impaired thermoregulatory responses to exercise are, at least partly, explained by the lower absolute workload and lower physical fitness level in heart failure patients

The Impact of Central and Peripheral Cyclooxygenase Enzyme Inhibition on Exercise-induced Core Body Temperature Elevations.

PURPOSE: Exercise increases core body temperature (TC) due to metabolic heat production. However, the exercise-induced release of inflammatory cytokines including interleukin-6 may also contribute to the rise in TC by increasing the hypothalamic temperature setpoint. We aimed to investigate whether the exercise-induced increase in TC is partly caused by an altered hypothalamic temperature setpoint. METHODS: 15 healthy, active male subjects aged 36±14 years were recruited. Subjects performed submaximal treadmill exercise in 3 randomized test conditions: (1) ibuprofen 400mg and acetaminophen 1000mg (IBU/APAP), (2) acetaminophen 1000mg (APAP) and (3) a control condition (CTRL). Acetaminophen and ibuprofen were used to block the effect of interleukin-6 at a central and peripheral level, respectively. TC, skin temperature and heart rate were measured continuously during the submaximal exercise tests. RESULTS: Baseline values of TC, skin temperature and heart rate did not differ across conditions. Serum interleukin-6 concentrations increased in all three conditions. A significantly lower peak TC was observed in IBU/APAP (38.8±0.4°C) versus CTRL (39.2±0.5°C, p=0.02), but not in APAP (38.9±0.4°C) versus CTRL. Similarly, a lower ΔTC was observed in IBU/APAP (1.7±0.3°C) versus CTRL (2.0±0.5°C, p<0.02), but not in APAP (1.7±0.5°C) versus CTRL. No differences were observed in skin temperature and heart rate responses across conditions. CONCLUSIONS: The combined administration of acetaminophen and ibuprofen resulted in an attenuated increase in TC during exercise when compared to a control condition. This observation suggests that a prostaglandin E2 induced elevated hypothalamic temperature setpoint may contribute to the exercise-induced rise in TC

Impact of prolonged walking exercise on cardiac structure and function in cardiac patients versus healthy controls.

BACKGROUND AND DESIGN: Previous studies have demonstrated that endurance exercise can cause an acute transient decrease in cardiac function in healthy subjects. Whether this also occurs in cardiac patients is unknown. We investigated the impact of prolonged single day and three-day walking exercise on cardiac function and cardiac biomarkers between cardiac patients and healthy controls in an observational study. METHODS: We recruited 10 cardiac patients (nine males, one female, 68 ± 5 years) and 10 age- and sex-matched healthy control subjects (nine males, one female, 68 ± 4 years) to perform 30 or 40 km of walking exercise per day for three consecutive days. Cardiac function was examined using echocardiography and cardiac biomarkers (cardiac troponin and B-type natriuretic peptide) with blood samples. Data were collected before walking and directly after walking on day 1 and day 3. RESULTS: Post-exercise early systolic tissue contraction velocity of the left ventricle (p = 0.005) and global longitudinal left ventricle strain (P = 0.026) were increased in both groups compared with baseline. Post-exercise right ventricle peak early diastolic tissue filling velocity and systolic blood pressure/left ventricle end-systolic volume ratio decreased in both groups (p = 0.043 and p = 0.028, respectively). Post-exercise cardiac troponin levels increased (p = 0.045) but did not differ across groups (p = 0.60), whereas B-type natriuretic peptide levels did not change (p = 0.43). CONCLUSION: This study suggests that stable cardiac patients are capable of performing three days of prolonged walking exercise without clinically significant acute overall deterioration in cardiac function or more pronounced increase in cardiac biomarkers compared with healthy controls

Cerebrovascular CO2 reactivity and dynamic cerebral autoregulation through the eighth decade of life and their implications for cognitive decline

Aging is accompanied by a decrease in cerebral blood flow (CBF), especially in the presence of preclinical cognitive decline. The role of cerebrovascular physiology including regulatory mechanisms of CBF in processes underlying aging and subclinical cognitive decline is, however, not fully understood. We explored changes in cerebrovascular CO2 reactivity and dynamic cerebral autoregulation (dCA) through the eighth decade of life, and their relation with early cognitive decline. After 10.9 years, twenty-eight (age, 80.0 ± 3.5 years; 46% female) out of forty-eight healthy older adults who had participated in a previous study (age at baseline, 70 ± 4 years; 42% female), underwent repeated transcranial Doppler assessments. Linear mixed-model analyses revealed small reductions in cerebrovascular CO2 reactivity with aging (-0.37%/mmHg, P = 0.041), whereas dCA was modestly enhanced (gain: -0.009 cm/s/mmHg, P = 0.038; phase: +8.9 degrees, P = 0.004). These changes were more pronounced in participants who had developed subjective memory complaints at follow-up. Our observations confirm that dCA is not impaired in aging, despite lower cerebral perfusion and cerebrovascular reactivity. Altogether, this unique longitudinal study highlights the involvement of cerebrovascular health in preclinical cognitive decline, which is of clinical relevance in the development of dementia management strategies

The impact of feedback during formative testing on study behaviour and performance of (bio)medical students: a randomised controlled study.

BACKGROUND: A potential concern of formative testing using web-based applications ("apps") is provision of limited feedback. Adopting a randomised controlled trial in 463 first year (bio) medical students, we explored if providing immediate, detailed feedback during "app"-based formative testing can further improve study behaviour and study performance of (bio)medical students. METHODS: Students had access to a formative testing "app", which involved 7 formative test modules throughout the 4-week course. In a randomised order, subjects received the "app" with (n = 231, intervention) or without (n = 232, control) detailed feedback during the formative test modules. RESULTS: No differences in app-use was found between groups (P = 0.15), whereas the intervention group more frequently reviewed information compared to controls (P = 0.007). Exam scores differed between non-/moderate-/intensive- users of the "app" (P  0.05). CONCLUSIONS: Providing detailed feedback did not further enhance the effect of a web-based application of formative testing on study behaviour or study performance in (bio)medical students, possibly because of a ceiling-effect