The effects of training status and exercise intensity on exercise-induced muscle damage.

BACKGROUND: Individuals participating in exercise beyond their level of fitness may be at higher risk for exercise-induced muscle damage, however the impact of training status on muscle damage development is not well understood. The purpose of this study was to measure skeletal muscle damage and soreness after five days of high and low intensity exercise in previously trained and untrained individuals. METHODS: Eighteen males and females (9 trained and 9 untrained) completed five consecutive days of high intensity (HI) exercise and five consecutive days of low intensity (LI) exercise. Blood was drawn at the initial visit and after completion of each exercise intensity period. RESULTS: CK was elevated post exercise for both groups during both intensities, but was greater in trained vs. untrained (HI: 203.6 vs. 143.4 IU/L and LI: 156.4 vs. 109.3 IU/L; P<0.01). Myoglobin was significantly higher after exercise for both groups (P<0.01) and was higher following high vs. low intensity in trained (P<0.01), but not untrained (P=0.052). Untrained experienced soreness following one day of high intensity exercise vs. after 3 days in trained participants (P=0.04, P=0.02). CONCLUSIONS: The current study suggests that high intensity exercise results in greater muscle damage in both trained and untrained individuals vs. low intensity exercise. However untrained participants experience more pain and with earlier onset and should therefore take caution when beginning exercise programs that require consecutive sessions of high intensity exercise.

Association of Sleep Quality With Cardiovascular Disease Risk and Mental Health in Law Enforcement Officers.

OBJECTIVES: The aim of the study was to determine whether sleep quality is associated with an increased risk for cardiovascular disease (CVD) or worsened mental health. METHODS: Self-reported sleep quality, 35 inflammatory factors, CVD risk factors, personal stress, police operational and organizational stress, social support, depressive symptoms, and health-related quality of life were compared among a cohort of officers. RESULTS: Of 379 officers, 39% and 27% had poor and borderline sleep quality. Sleep quality was not associated with either an altered inflammatory profile or worsened CVD risk factors. Compared with good sleepers, borderline and poor sleepers reported increased personal stress, police organizational and operational stress, and depressive symptoms, but decreased health-related quality of life. CONCLUSIONS: Poor sleep quality is prevalent in the law enforcement profession and is associated with worsened mental health but not with an increased risk for CVD.

Alkaloids and athlete immune function: caffeine, theophylline, gingerol, ephedrine, and their congeners.

Plant alkaloids are found in foods, beverages, and supplements consumed by athletes for daily nutrition, performance enhancement, and immune function improvement. This paper examined possible immunomodulatory roles of alkaloids in exercise contexts, with a focus on human studies. Four representative groups were scrutinized: (a) caffeine (guaranine, mateine); (b) theophylline and its isomers, theobromine and paraxanthine; (c) ginger alkaloids including gingerols and shogaol; and (d) ephedra alkaloids such as ephedrine and pseudoephedrine. Emerging or prospective alkaloid sources (Goji berry, Noni berry, and bloodroot) were also considered. Human in vitro and in vivo studies on alkaloids and immune function were often conflicting. Caffeine may be immunomodulatory in vivo depending on subject characteristics, exercise characteristics, and immune parameters measured. Caffeine may exhibit antioxidant capacities. Ginger may exert in vivo anti-inflammatory effects in certain populations, but it is unclear whether these effects are due to alkaloids or other biochemicals. Evidence for an immunomodulatory role of alkaloids in energy drinks, cocoa, or ephedra products in vivo is weak to nonexistent. For alkaloid sources derived from plants, variability in the reviewed studies may be due to the presence of unrecognized alkaloids or non-alkaloid compounds (which may themselves be immunomodulatory), and pre-experimental factors such as agricultural or manufacturing differences. Athletes should not look to alkaloids or alkaloid-rich sources as a means of improving immune function given their inconsistent activities, safety concerns, and lack of commercial regulation.

Herbal supplements and athlete immune function--what's proven, disproven, and unproven?

The purpose of this paper is to critically evaluate current immunological and clinical literature regarding the effects of herbal preparations on athlete immune function. First, we review rates of herbal supplement use by athletes. Second, we use ginseng (Panax ginseng) and coneflower (Echinacea spp.) as models for examining how herbal supplements may influence immune function within the contexts of exercise and sport, while briefly considering several other popular herbal products. Third, we proffer several evidence-based hypotheses to explain apparent discrepancies among the cumulative data, concomitantly advancing a novel conceptual framework which may be useful to understanding herbal supplements and athlete immune function using Echinacea supplements as a model. Fourth, we apply the proposed framework to some prospective data regarding the effects of Echinacea pallida and Echinacea simulata on in vitro cytokine production and cell proliferation in peripheral blood mononuclear cells collected from male collegiate wrestlers and soccer players during training. Fifth and finally, we evaluate the current knowledge on herbal supplements and athlete immune function, identify gaps and limitations in knowledge, and advance several possible options for future research.

Human blood mononuclear cell in vitro cytokine response before and after two different strenuous exercise bouts in the presence of bloodroot and Echinacea extracts.

The purpose of this multidisciplinary investigation was to characterize cytokine production by human blood mononuclear cells after 2 contrasting exercise bouts (a maximal graded oxygen consumption [VO(2)max] test and 90 min of cycling at 85% of ventilatory threshold [VT]) when stimulated in vitro with extracts from bloodroot (Sanguinaria canadensis), coneflower (Echinacea tennesseensis), or solvent vehicle controls. Blood was sampled pre- and post-exercise. Production of TNF, IL-1beta, and IL-10 were measured at 24, 48, and 72 h, respectively. In the VO(2)max test there was a main effect of exercise such that exercise increased cytokine synthesis and a main effect of stimulant such that bloodroot extracts significantly increased cytokine production compared to other stimulants or controls. In the 90-min bout, there was a main effect of exercise for TNF and IL-1beta (but not IL-10) such that exercise decreased cytokine synthesis and a main effect of stimulant such that bloodroot extracts significantly increased cytokine production compared to other stimulants or controls, with exercisexstimulant interactions for both IL-1beta and IL-10. A similar though weaker effect was seen with Echinacea extracts; subsequent biochemical analyses suggested this was related to alkamide decay during 3 years undisturbed storage at ultralow (-80 degrees C) temperature. In this study, the VO(2)max test was associated with enhanced cytokine production whereas the 90-min cycling at 85% VT was associated with suppressed cytokine production. Bloodroot extracts were able to increase cytokine production in both contexts. Herbal extracts purported to offset exercise-associated effects on immune activity warrant continued investigation.