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Purpose: The randomized controlled OptiTrain trial showed beneficial effects on fatigue after a 16-wk exercise intervention in patients with breast cancer undergoing adjuvant chemotherapy. We hypothesize that exercise alters systemic inflammation and that this partially mediates the beneficial effects of exercise on fatigue., Methods: Two hundred and forty women scheduled for chemotherapy were randomized to 16 wk of resistance and high-intensity interval training (RT-HIIT), moderate-intensity aerobic and high-intensity interval training (AT-HIIT), or usual care (UC). In the current mechanistic analyses, we included all participants with >60% attendance and a random selection of controls (RT-HIIT = 30, AT-HIIT = 27, UC = 29). Fatigue (Piper Fatigue Scale) and 92 markers (e.g., interleukin-6 [IL-6] and tumor necrosis factor α [TNF-α]) were assessed at baseline and postintervention. Mediation analyses were conducted to explore whether changes in inflammation markers mediated the effect of exercise on fatigue., Results: Overall, chemotherapy led to an increase in inflammation. The increases in IL-6 (pleiotropic cytokine) and CD8a (T-cell surface glycoprotein) were however significantly less pronounced after RT-HIIT compared with UC (-0.47, 95% confidence interval = -0.87 to -0.07, and -0.28, 95% confidence interval = -0.57 to 0.004, respectively). Changes in IL-6 and CD8a significantly mediated the exercise effects on both general and physical fatigue by 32.0% and 27.7%, and 31.2% and 26.4%, respectively. No significant between-group differences in inflammatory markers at 16 wk were found between AT-HIIT and UC., Conclusions: This study is the first showing that supervised RT-HIIT partially counteracted the increase in inflammation during chemotherapy, i.e., IL-6 and soluble CD8a, which resulted in lower fatigue levels postintervention. Exercise, including both resistance and high-intensity aerobic training, might be put forward as an effective treatment to reduce chemotherapy-induced inflammation and subsequent fatigue., (Copyright © 2020 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of the American College of Sports Medicine.)

Objective: To investigate whether thyroid function profiles can predict poststroke fatigue (PSF) in patients with acute ischemic stroke., Methods: Patients with stroke were consecutively recruited within 3 days of onset in Jinling Hospital. Serum levels of thyroid hormones, thyroid antibodies, hematologic indexes, and biochemical indexes were measured on admission. Fatigue was scored using the Fatigue Severity Scale. Associations were analyzed with multivariate regression and restricted cubic splines., Results: Of the 704 patients with stroke, 292 (41.5%) were diagnosed with fatigue in the acute stage and 224 (35.3%) 6 months after the index stroke. The serum levels of thyroid-stimulating hormone (TSH) were inversely associated with the risk of PSF in both the acute phase and at follow-up evaluations after adjusting for potential confounders (odds ratio 0.30, 95% confidence interval 0.24-0.37 in the acute phase, and odds ratio 0.70, 95% confidence interval 0.58-0.84 at follow-up). The subgroup analysis indicated that in the acute phase of ischemic stroke, TSH was associated with severity of PSF in the groups with euthyroidism (β = -0.70, p < 0.001), subclinical hypothyroidism (β = -0.44, p < 0.001), and low-T 3 syndrome (β = -0.34, p = 0.008). Higher TSH was associated with better Fatigue Severity Scale scores in patients with low-T 3 syndrome 6 months after the index stroke (β = -0.35, p = 0.01). Furthermore, in the group with low-T 3 syndrome, FT 3 serum level could also indicate a higher risk of PSF (β = -2.54, p < 0.001 in the acute phase, and β = -2.67, p < 0.001 at follow-up)., Conclusion: Thyroid function profiles may predict fatigue after acute ischemic stroke, suggesting that neuroendocrine responses could have a role in PSF., (© 2018 American Academy of Neurology.)

Background: Fatigue remains a prevalent, persistent, and debilitating side effect of chemotherapy for stage I and II breast cancer patients. Severity of fatigue varies among patients. Evidence suggests that proinflammatory cytokines contribute to the development of fatigue., Objective: The aim of this study is to investigate predictors of fatigue and cytokine levels in women undergoing chemotherapy for stage I or II breast cancer., Methods: Piper Fatigue Scales and blood samples for interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) levels were collected at baseline and days 7, 14, and 21 for each chemotherapy cycle. Descriptive statistics, general linear mixed models, and graphic analysis were used to analyze the data., Results: The predominantly white convenience sample was composed of 11 women with stage I or II breast cancer who were 37 to 72 years old (mean, 52 years). Predictors of fatigue were type of chemotherapy drugs, time, and IL-6 levels. A predictor of IL-6 and TNF-α levels was whether chemotherapy was administered at the visit. Type of chemotherapy significantly predicted TNF-α levels. Fatigue patterns were characterized by chaotic pattern of peaks and troughs unique to each woman., Conclusions: Women with stage I and II breast cancer experienced variability in the severity of fatigue and levels of IL-6 and TNF-α throughout their treatment trajectories. The presence and role of genetic variants related to cancer-related fatigue may explain the individual variation and warrant further research., Implications for Practice: These findings highlight the importance of symptom assessments including fatigue at each clinic visit and individualized interventions throughout the cancer trajectory.

Rationale: Following prolonged endurance events such as marathons, elevated levels of cardiospecific biomarkers are commonly reported. Although transiently raised levels are generally not considered to indicate clinical myocardial damage, comprehension of this phenomenon remains incomplete. The popularity of high-intensity interval training highlights a paucity of research measuring cardiac biomarker response to this type of exercise. This a posteriori case report discusses the elevation of cardiac troponins (cTn) associated with short interval, high-intensity exercise., Patient Concerns: In this case report, an apparently healthy 29-year-old recreationally active female presented clinically raised cardiac troponin I (cTnI) levels (>0.04 ng/mL), after performing high-intensity cycle ergometer sprints. As creatine kinase (CK) is expressed by multiple organs (e.g., skeletal muscle, brain, and myocardium), cTnI assays were performed to determine any changes in total serum CK levels not originating from skeletal muscle damage., Diagnosis: A posteriori the individual's daily energy expenditure indicated chronically low-energy availability. Psychometric testing suggested that the individual scored positive for disordered eating, highly for fatigue levels, and low in mental health components., Outcomes: The current case report provides novel evidence of elevated cTnI occurring as a result of performing short duration, high intensity, cycle ergometer exercise in an individual with self-reported chronically depleted energy balance. A schematic to identify potentially "at risk" individuals is presented., Lessons: Considering this as a case report, results cannot be generalized; however, the main findings suggest that individuals who habitually restrict their calorie intake below their bodies' daily energy requirements, may have elevated biomarkers of exercise induced myocardial stress from performing high-intensity exercise.

Background: Fatigue is one of the most debilitating adverse effects of cancer therapy. Identifying biomarkers early during cancer therapy may help us understand the biologic underpinnings of the persistence of fatigue following therapy., Objective: We aimed to identify early biomarkers of fatigue by examining correlations of levels of cytokines during external beam radiation therapy (EBRT) with persistence of fatigue 1 year following treatment completion in men with nonmetastatic prostate cancer (NM-PC)., Methods: A sample of 34 men with nonmetastatic prostate cancer scheduled to receive EBRT were followed up at baseline (T1), midpoint of EBRT (T2), and 1 year following EBRT (T3). Demographic and clinical data were obtained by chart review. The Functional Assessment of Cancer Therapy-Fatigue was administered to measure fatigue levels. Plasma cytokine levels were determined at T1 and T2 using the Bio-Rad Bio-Plex Cytokine Assay Kits., Results: Significant correlations were observed between levels of interleukin 2 (IL-3), IL-8, IL-9, IL-10, IL-16, interferon γ-induced protein 10, interferon α2, interferon γ, and stromal cell-derived factor 1α at T2 with worsening of fatigue from T1 to T3., Conclusions: Immunological changes prior to chronic fatigue development may reflect the long-term response to radiation therapy-induced damage., Implications for Practice: Early biomarkers for chronic fatigue related to cancer therapy will help advance our understanding of the etiology of this distressing symptom and will help nurses identify patients at risk of developing chronic fatigue after cancer treatment. This information will also aid in patient education, as well as symptom management.

Low serum levels of vitamin D have been associated with fatigue in both healthy and clinical populations. Our aim was to evaluate the effect of vitamin D supplementation on fatigue in kidney transplant recipients (KTRs). In total, 137 patients after kidney transplant and 119 age- and sex-matched healthy volunteers were recruited. Serum levels of 25-hydroxyvitamin D (25(OH)D) were measured by competitive protein-binding assay. Fatigue was assessed using the subscale fatigue of the Checklist Individual Strength (CIS). Of all KTRs, 60 patients without initial vitamin D3 supplementation were started on vitamin D3 supplementation (cholecalciferol) 800 IU/d, with a follow-up examination after 3.0 to 9.0 months (mean, 6 months). Fatigue was found in 40.1% of KTRs. Serum 25(OH)D levels were inversely and independently associated with CIS scores in KTRs (P = .002). In the 60 patients who received vitamin D3 supplementation, 25(OH)D was overall increased at follow-up with 18.5% (P = .004) and CIS scores improved with 10.0% (P = .007). As vitamin D has beneficial effects on fatigue scores in KTRs, we suggest monitoring this parameter in KTRs and supplementation with vitamin D3 when vitamin D levels are low.

Background: Symptom distress often occurs in lung cancer patients undergoing chemotherapy. However, a biomarker has not been identified to reflect the severity of their symptom distress., Objective: The aim of this study was to investigate the relationship between symptom distress and serum inflammatory biomarkers in lung cancer patients undergoing chemotherapy., Methods: A longitudinal, repeated-measures design was used to assess subjective symptoms (fatigue, sleep disturbance, pain, depression, and confusion), serum biomarkers (tartrate-resistant acid phosphatase 5a [TRACP5a], interleukin 6 [IL-6], IL-8, and C-reactive protein), and white blood cells in 62 lung cancer patients recruited from a single medical center at 3 time points: T1 was the baseline, T2 was the eighth day after the first chemotherapy cycle, and T3 was prior to the second cycle. Symptom distress was measured individually by 5 questionnaires (General Fatigue Scale, Pittsburgh Sleep Quality Index, Brief Pain Inventory, Profile of Mood States-Depressive, and Confusion)., Results: The trend of TRACP5a was positively correlated to the trend of the patients' symptom distress. However, the trends of IL-6 and IL-8 did not correlate., Conclusions: Serum TRACP5a was associated with symptom distress in lung cancer patients. Therefore, TRACP5a might be a potential biomarker to assess symptom distress of lung cancer patients undergoing chemotherapy., Implications for Practice: Oncology nurses may be able to apply TRACP5a expression to predict or monitor multiple distress symptoms in lung cancer patients undergoing chemotherapy. Furthermore, nurses can use these study findings to better understand the patients who need more attention to improve their quality of life.

Objective: Given the importance of positive affect and inflammation for well-being in cancer survivors, the current study examined the relationship between high- and low-arousal positive affect and inflammation in 186 women who completed treatment of early-stage breast cancer., Methods: Measures of high- and low-arousal positive affect were completed within 3 months after treatment completion (baseline). Plasma markers of inflammation, including soluble tumor necrosis factor receptor type II (sTNF-RII), C-reactive protein (CRP), and interleukin-1 receptor antagonist, were assessed at baseline and 6- and 12-month follow-up assessments., Results: Multilevel modeling analyses showed that high-arousal positive affect was associated with lower levels of sTNF-RII, a marker of TNF activity, at treatment completion and prospectively predicted maintenance of these differences through the 6- and 12-month follow-ups adjusting for biobehavioral confounds (b = -0.055, t(156) = -2.40, p = .018). However, this association was no longer significant when adjusting for fatigue. Exploratory analyses showed that low-arousal positive affect was associated with lower levels of CRP at treatment completion and through the 6- and 12-month follow-ups; this association remained significant after adjusting for fatigue and other confounds (b = -0.217, t(152) = -2.04, p = .043)., Conclusions: The relationship of high-arousal positive affect (e.g., "active") with sTNF-RII seems to be driven by the overlap of high-arousal positive affect with fatigue, whereas the relationship of low-arousal positive affect (e.g., "calm") with CRP was independent of fatigue. Future research should consider affective arousal when examining the association of positive affect with inflammation as this facet of positive affect may have important implications for interpretation of results.

Objective: Depression and inflammation may independently promote breast cancer (BCa) disease progression and poorer clinical outcomes. Depression has been associated with increased levels of inflammatory markers in medically healthy individuals and patients with cancer. However, inconsistencies in study time frames complicate interpretation of results within specific cancer types. This study examined relationships between depressive symptoms and inflammation in women with early-stage BCa before beginning adjuvant treatment., Methods: Women with Stage 0-III BCa were recruited approximately 4 to 8 weeks after surgery. Depressive symptoms were assessed using the Hamilton Rating Scale for Depression, and blood samples were collected to quantify circulating levels of interleukin (IL)-1β, IL-6, and tumor necrosis factor α (TNF-α) by enzyme-linked immunosorbent assay. Analyses of covariance were used to test for group differences (elevated versus low depressive symptoms) in levels of cytokines. Multiple regression analyses were used to examine relationships between continuous severity of depressive symptoms and levels of cytokines adjusting for relevant biobehavioral covariates., Results: Thirty-six (40%) of 89 patients showed elevated levels of depressive symptoms and, in adjusted models, had marginally higher levels of IL-1β (mean [M] = 14.49 [95% confidence interval {CI} = 6.11-32.65] versus M = 4.68 [95% CI = 1.96-9.86] and IL-6 [M = 88.74 {95% CI = 33.28-233.96} versus M = 61.52 {95% CI = 27.44-136.40}]) significantly higher levels of TNF-α (M = 17.07 [95% CI = 8.27-34.32] versus M = 6.94 [95% CI = 3.58-12.80]) than did women with low depressive symptoms. Across the spectrum of depressive symptoms, greater magnitude of depressive symptoms was related to greater levels of IL-1β (β = 0.06, p = .006, R = 0.25) and TNF-α (β = 0.06, p = .003, R = 0.27)., Conclusions: Postsurgery and preadjuvant treatment for early-stage BCa, depressive symptoms covary with elevated levels of multiple proinflammatory cytokines. Findings have implications for psychosocial and biological interventions concurrently focusing on depression and inflammation., Trial Registration: NCT01422551.

Objectives: High serum level of interleukin 6 (IL-6) is associated with high degree of tumor progression and systemic weakness. Anti-IL-6 therapy possibly improves the deterioration of clinical characteristics in patients with high IL-6 level. However, IL-6-related factors in patients with treatment-naive advanced pancreatic cancer (PC) have not been established. The goal of this study was to identify IL-6-related factors in patients with advanced PC who were scheduled to undergo first-line chemotherapy., Methods: Patients with treatment-naive advanced PC were eligible for inclusion in this study. Patients who did not receive first-line chemotherapy were excluded. Serum IL-6 levels and clinical parameters were prospectively recorded. Analyses were performed to identify risk factors for high IL-6 levels., Results: Eighty patients were analyzed. IL-6-related factors were advanced age (P < 0.01), the presence of liver metastasis (P < 0.01), the large volume of liver metastasis (P < 0.01), severe fatigue (P = 0.02), high carcinoembryonic antigen levels (P = 0.02), anemia (P < 0.01), and high C-reactive protein levels (P = 0.02) in multivariate analyses. Decreased skeletal muscle mass tended to be associated with high IL-6 levels., Conclusions: High serum IL-6 was related to advanced age, the presence of hepatic metastasis, large tumor burden in liver, severe fatigue, high carcinoembryonic antigen, high C-reactive protein, and anemia in patients with treatment-naive advanced PC.

Purpose: To examine the effects of three different frequencies of combined resistance and aerobic training on total energy expenditure (TEE) and activity-related energy expenditure (AEE) in a group of older adults., Methods: Seventy-two women, 60-74 yr old, were randomly assigned to one of three groups: 1 d · wk(-1) of aerobic training and 1 d · wk(-1) of resistance training (1 + 1), 2 d · wk(-1) of aerobic training and 2 d · wk(-1) resistance training (2 + 2), or 3 d · wk(-1) of aerobic training and 3 d · wk(-1) of resistance training (3 + 3). Body composition (dual-energy x-ray absorptiometry), feeling of fatigue, depression, and vigor (questionnaire), strength (one-repetition maximum), serum cytokines (enzyme-linked immunosorbent assay), maximal oxygen uptake (progressive treadmill test), resting energy expenditure, and TEE were measured before and after 16 wk of training. Aerobic training consisted of 40 min of aerobic exercise at 80% maximum heart rate, and resistance training consisted of two sets of 10 repetitions for 10 different exercises at 80% of one repetition maximum., Results: All groups increased fat-free mass, strength, and aerobic fitness and decreased fat mass. No changes were observed in cytokines or perceptions of fatigue/depression. No time-group interaction was found for any fitness/body composition variable. TEE and AEE increased with the 2 + 2 group but not with the other two groups. Nonexercise training AEE (nonexercise training activity-related thermogenesis) increased significantly in the 2 + 2 group (+200 kcal · d(-1)), group 1 + 1 showed a trend for an increase (+68 kcal · d(-1)), and group 3 + 3 decreased significantly (-150 kcal · d(-1))., Conclusion: Results indicate that 3 + 3 training may inhibit nonexercise training activity-related thermogenesis by being too time consuming and does not induce superior training adaptations to 1 + 1 and 2 + 2 training.

Fatigue is the most frequent symptom experienced by children/adolescents with cancer. One mechanism contributing to cancer-related fatigue involves abnormalities in adenosine triphosphate synthesis caused by carnitine deficiency. The purpose of this study was to examine fatigue and carnitine in children/adolescents before and after ifosfamide, cisplatin, or doxorubicin chemotherapy. Sixty-seven patients from 2 children's cancer centers participated. Fatigue and carnitine measures were obtained before chemotherapy and a week later. Newly diagnosed children/adolescents had significantly higher free (P=0.018) and total carnitine levels (P=0.017) compared with those who received prior chemotherapy. There was a significant increase in free and total carnitine levels after treatment for patients receiving doxorubicin than patients receiving cisplatin or ifosfamide. Increased fatigue and decreased carnitine were significantly correlated a week after chemotherapy in children/adolescents who had received prior chemotherapy. Increased carnitine in newly diagnosed patients is likely associated with rapid tissue release into the bloodstream, replacing carnitine lost by chemotherapy metabolism. Decreased carnitine and increased fatigue occurred after 1 to 2 courses of chemotherapy. This study provides support for a relationship between carnitine and fatigue in children/adolescents with cancer.

Background: In animal studies and a pilot trial in patients with congestive heart failure, the thyroid hormone analog 3,5 diiodothyropropionic acid (DITPA) had beneficial hemodynamic effects., Methods and Results: This was a phase II multicenter, randomized, placebo-controlled, double-blind trial of New York Heart Association class II to IV congestive heart failure patients randomized (2:1) to DITPA or placebo and treated for 6 months. The study enrolled 86 patients (n=57 to DITPA, n=29 to placebo). The primary objective was to assess the effect of DITPA on a composite congestive heart failure end point that classifies patients as improved, worsened, or unchanged based on symptom changes and morbidity/mortality. DITPA was poorly tolerated, which obscured the interpretation of congestive heart failure-specific effects. Fatigue and gastrointestinal complaints, in particular, were more frequent in the DITPA group. DITPA increased cardiac index (by 18%) and decreased systemic vascular resistance (by 11%), serum cholesterol (-20%), low-density lipoprotein cholesterol (-30%), and body weight (-11 lb). Thyroid-stimulating hormone was suppressed in patients given DITPA, which reflects its thyromimetic effect; however, no symptoms or signs of potential hypothyroidism or thyrotoxicosis were seen., Conclusions: DITPA improved some hemodynamic and metabolic parameters, but there was no evidence for symptomatic benefit in congestive heart failure.

Purpose: The purpose of this study was to examine the effect of carbohydrate supplementation on differentiated and undifferentiated ratings of perceived exertion (RPE) during prolonged intermittent exercise and recovery., Methods: Twelve male subjects cycled for 2.0 h at 64% Wmax and 73% V O2peak with 3-min rest intervals interspersed every 10 min (2.6 h of total exercise time, including rest intervals) with placebo (P) or carbohydrate (C) beverages. RPE was assessed during the last minute of each 10-min exercise interval and then every 30 s during the 3-min recovery period., Results: The pattern of change in RPE over time was significantly different between C and P ingestion (P < 0.05), with attenuated RPE responses found for both overall body (O) and legs (L). A significant main effect was found for recovery RPE-O between C and P ingestion (P < 0.05), with attenuated RPE responses found in the later part of the 2-h run. C relative to P ingestion was associated with higher respiratory exchange ratios and plasma levels of glucose and with lower levels of plasma cortisol., Conclusions: These data indicate that carbohydrate supplementation attenuates perceived exertion during prolonged intermittent exercise and recovery.

The authors analyzed muscle biopsy specimens of 104 patients with creatine kinase activity greater than 500 UI/L (normal 10 to 170 UI/L) without signs of muscle weakness. They achieved a definite or probable diagnosis in 55% of cases. The most frequently identified diseases were glycogen storage diseases, muscular dystrophies, and inflammatory myopathies. The probability of making a diagnosis was higher in children and when creatine kinase level was greater than 2,000 UI/L.

Objective: Sustained psychological stress may result in a state operationalized as "vital exhaustion." Exhaustion predicted coronary artery disease (CAD) events whereby increased inflammatory activity might mediate this link. Moreover, there is an emerging importance of gene-environmental interactions in CAD. We investigated the effect of exhaustion severity on plasma levels of C-reactive protein (CRP) and whether exhaustion might regulate CRP levels via the -308G/A polymorphism of the tumor necrosis factor (TNF)-alpha gene., Methods: We assessed exhaustion in 275 industrial employees (mean age +/- SD, 41 +/- 9 years, 88% men) using the Maastricht Questionnaire. Subjects were stratified as per exhaustion severity: none (N = 80), moderate (N = 128), and severe (N = 67). The TNF-alpha polymorphism was determined by real-time polymerase chain reaction, and plasma CRP levels were measured by a high-sensitivity immunoassay., Results: There was a significant interaction between exhaustion and the TNF-alpha polymorphism, explaining 4.5% in the variance of plasma CRP values (F(5,271) = 2.47, p =.033); the result held after controlling for classic cardiovascular risk factors. Adjusted mean CRP levels across exhaustion strata in GA (N = 70) and AA (N = 3) carriers combined were 0.91 mg/l (none), 1.78 mg/l (moderate), and 2.61 mg/l (severe) as compared with 1.24 mg/l, 1.61 mg/l, and 1.36 mg/l for the GG wild-type (N = 202)., Conclusion: The findings suggest that the A allele of the TNF-alpha -308 G/A polymorphism may mediate inflammation with exhaustion in a dose-response relationship, while with the GG wild-type exhaustion severity seems unrelated to CRP levels. The finding provides a rationale for gene-environmental interactions by which psychosocial factors may promote atherosclerosis and CAD.

Objective: Infections with herpes viruses have been implicated in the pathogenesis of atherosclerosis. We tested the hypothesis that vital exhaustion (VE) is associated with multiple herpesvirus infections, such as herpes simplex virus, varicella-zoster virus, Epstein-Barr virus, and cytomegalovirus, and with an increase in pathogen burden (ie, the aggregated seropositivity to immunoglobulin G antibodies for herpes simplex virus, varicella-zoster virus, Epstein-Barr virus, and cytomegalovirus). In addition, we examined the association of VE and pathogen burden with measures of hemostasis and inflammation., Methods: Blood samples were drawn from 29 men with VE and 30 male control subjects, all healthy and nonsmokers, to assess serological evidence of infection and measures of hemostasis and inflammation., Results: VE is associated with a relatively high pathogen burden, altered hemostasis, and higher levels of cytokines, such as interleukin-6. Across all subjects, a relatively high pathogen burden was also associated with altered hemostasis but not with increased cytokine levels. The interaction of VE with pathogen burden revealed significant linear increases in measures of hemostasis and inflammation. Finally, immunoglobulin G antibody titer levels of individual herpesvirus infections were not associated with hemostatic measures or with cytokines., Conclusions: We conclude that stress-related alterations in hemostasis and inflammation are not necessarily linked to one particular herpesvirus infection but rather to an increase in aggregated seropositivity to herpesvirus infections.

The use of megadoses of vitamin and mineral supplements has become common. The authors describe a 17-year-old boy who presented with fatigue after taking large daily doses of zinc supplements for 6 to 7 months in an attempt to treat his acne. A zinc-induced hypocupremia developed, causing anemia, leukopenia, and neutropenia. Anemia and neutropenia resolved 6 months after he stopped taking the zinc. Excessive zinc intake can have toxic effects, and questions about patients' use of vitamin and mineral supplements should be asked when medication histories are taken.

Purpose: A longitudinal biological study of 20 elite rowers was performed using capillary blood (serum) FT-IR spectra to evaluate their training load adaptations and fatigue., Methods: Difference spectra (rest serum spectra subtracted to exercise serum spectra) were used to evaluate subjects' metabolic response to exercise. Spectra classifications were used for serum contents differentiation on the basis of biomolecular absorption., Results: For two subjects, several metabolic differentiations were observed. These started with sugars metabolism on the fifth training week, followed successively by lipid metabolism and protein metabolism, when overtraining was clinically diagnosed. Several weeks further into the training program, the same onset of metabolic differentiations was observed for eight other subjects. When differentiations reached lipid metabolism, they were asked to reduce their training loads. Unlike the overtrained subjects, a rapid recovery was observed (3 vs 22 wk) and metabolism alterations disappeared., Conclusion: The fatigability limit in sportsmen seemed to be situated at a certain level of metabolic stress, beyond which a rapid overtraining process recover was no longer possible.

Physiological and mood state parameters were monitored during a 6-month swimming season in an attempt to determine markers of overtraining and recovery. Fourteen elite male and female swimmers were tested early-, mid-, and late-season and shortly before and after major competition. Training details and subjective ratings of well-being were compiled by the athletes in daily logs. Three swimmers were classified as stale based upon performance deterioration and prolonged, high fatigue levels. Staleness scores were calculated for each athlete using performance change from early- to late-season and daily fatigue ratings for the season. Regression analysis revealed a battery of well-being ratings which predicted staleness scores, accounting for 76% of the variance. The late-season stress ratings and plasma catecholamine levels at rest predicted staleness scores, accounting for 85% of the variance. During tapering, well-being ratings predicted improvement in competitive performance, accounting for 72% of the variance of the improvement in race times from previous best times. It was concluded that self-reported ratings of well-being may provide an efficient means of monitoring both overtraining and recovery; plasma catecholamine levels at rest may provide an additional objective tool for diagnosis.

The present study was designed to investigate EMG activities and ground reaction forces during fatigued and nonfatigued running. Ten male sprint runners volunteered to run a maximal 20-m speed test, a 400-m time trial, and submaximal 20-m runs at the average speed of the first 100 m of the 400 m. During the latter stage of each run, ground reaction forces and EMG activity of four leg muscles were recorded. EMG activities were time averaged during three phases of running: preactivation, braking, and propulsion phase. The resultant ground reaction forces both in the braking (P < 0.001) and in the propulsion phase (P < 0.01) were greater in the maximal and submaximal 20 m than at the end of the 400 m. The averaged EMG during the braking phase (P < 0.01) and during the total ground phase (P < 0.05) was smaller in the submaximal 20 m than at the end of the 400 m. On the other hand the averaged EMG was greater during the maximal 20 m than at the end of the 400 m during the propulsion phase (P < 0.001) and during the total ground phase (P < 0.05). In addition, the more the preactivity increased the less the resultant ground reaction force decreased in the braking phase during the 400 m run (r = 0.77, P < 0.05). It was concluded that the role of the increased neural activation was to compensate for muscular fatigue and the preactivation had an important role in maintaining force production during the 400-m run. In addition, the fatigue was different in each working muscle.

Fourteen elite swimmers had measurements of stress hormones taken at five points during a 6-month season: early-, mid- and late-season, during tapering for National Trials, and 1-3 d after the Trials. Training details and subjective ratings of fatigue were recorded daily in log books. Plasma norepinephrine and epinephrine concentrations were significantly correlated with swim training volume (r = 0.37 and 0.33, respectively, P < 0.05 for each). No significant differences were seen in norepinephrine or cortisol concentrations at the five sampling times. Epinephrine levels were significantly lower (P < 0.05) after competition compared with values early in the season and shortly before competition. Symptoms of the overtraining syndrome were identified in three of the swimmers, based on performance decrements and high, prolonged levels of fatigue. In these three swimmers, norepinephrine levels tended to be higher than those of the other swimmers from mid-season onward and were significantly higher (P < 0.01) during tapering. If these findings can be confirmed in larger numbers and different types of athletes, norepinephrine level may provide a useful marker of the overtraining syndrome.

Male Wistar rats were studied to determine if exercise training reduces the insulin response to sustained hyperglycemia. Training (TN) for 8 wk on a treadmill resulted in significantly (P less than 0.05) increased time to exhaustion in TN compared to control animals (CN). Hyperglycemic glucose clamps at 11 mM for 90 min resulted in elevations of arterial plasma insulin to 23.6 +/- 4.3 ng.ml-1 (mean +/- SE, N = 7) in CN and 11.8 +/- 1.1 ng.ml-1 (N = 7) in TN (P less than 0.05). No significant difference between groups existed for the level of imposed hyperglycemia. Glucose infusion rates required to maintain the sustained hyperglycemia were 62.7 +/- 3.2 mg.kg-1 min-1 in CN and 68.5 +/- 3.0 mg.kg-1.min-1 in TN (P greater than 0.05) at the end of the glucose clamp. These data show that exercise training reduces the insulin response to sustained steady state hyperglycemia.

The present study has compared the metabolic and cardiorespiratory responses for two groups of male subjects during 20 min of exercise at the anaerobic threshold (AT), at AT + 1/3, and at AT + 2/3 of the difference (delta) between AT and VO2max. A log-log transformation of the lactate (LA)-power output relationship was used to define AT and divide subjects into a high (N = 7, AT = 51.9 +/- 1.5% VO2max) and low (N = 5; AT = 41.9 +/- 1.8% VO2max) AT group. No differences were observed between groups during exercise at AT for VE.VO2-(1), VE.VCO2(-1), pH, pCO2, blood LA, and plasma strong ions Na+, K+, and Cl-. Although blood LA values were significantly elevated for the low AT subjects (2.3 +/- 0.6 mmol.l-1) compared with the high AT group (1.0 +/- 0.1 mmol.l-1) during exercise at AT + 1/3 delta, no other differences between groups were noted. In contrast, marked differences were observed between groups during exercise at AT + 2/3 delta. The high AT group showed no change in VE (79.1 +/- 4.8 l.min-1), pH (7.367 +/- 0.01), pCO2 (37.3 +/- 1.2 mm Hg), and blood LA (2.9 +/- 0.3 mmol.l-1) during the final 10 min of the 20 min exercise test.(ABSTRACT TRUNCATED AT 250 WORDS)