Agreement between session RPE and individual training impulse across a range of running speeds

BACKGROUND: The training impulse (TRIMP) provides a means of quantifying training dose during physical training; it is traditionally based on the heart rate response to exercise and involves establishing the heart rate – blood lactate relationship. A new approach is based on the individual’s global rating of perceived exertion (RPE) for the training session. The current study was undertaken to examine agreement between individual TRIMP and session RPE. METHODS: Nine healthy male volunteers completed three trials involving a 6 km treadmill run at speeds of 12 km×h-1, 9 km×h-1 and 7.2 km×h-1 in random order. Individual training impulse and session rating of perceived exertion were calculated for each trial. RESULTS: While both methods resulted in values increasing as the intensity of the trials increased there were no significant differences between the three trials for either method. There was a significant correlation between the two methods (N.=27) (r = 0.62, P<0.01) and the 95% limits of agreement lay between 27.34 and -107.42. Session rating of perceived exertion resulted in higher values for 24 of the 27 trials with the three giving higher individual training impulse all being during the lower training dose trials. CONCLUSIONS: The findings indicate that while the two methods are related there is a progressive increase in the disagreement as the training dose increases. Which of the two methods gives the better relationship with physiological adaptation has yet to be determined

Telic-paratelic Dominance and State Effects on Responses to Resistance and Endurance Exercise

We examined the influence of opposite states of mind (the “telic” vs. “paratelic” state) and dominances (personality characteristics that reflect a preference for one of these states) on emotion and stress responses to exercise. Telic dominant participants completing resistance exercise in the telic state condition reported decreased relaxation from pre- to post-exercise. All participants reported more pleasant emotions when performing endurance exercise in the telic state condition. In contrast, in the paratelic state condition, they reported increased anxiety. These results lend mixed support for previous research but suggest that meta-motivational state is more influential than dominance.fals

A 15-week vitamin D supplementation and indoor cycling intervention reduces exercising heart rate, with no effect on glycaemic control in healthy adults: A pilot investigation

Significant positive correlations are often observed between vitamin D concentrations and physical activity levels. Whilst this may be due to individuals who are physically active spending time outdoors (i.e. increased opportunity for vitamin D synthesis), there is growing evidence to suggest a more complex relationship between vitamin D status, physical fitness and health outcomes. To explore this further thirty-nine healthy adults were randomly allocated to 15 weeks of exercise training (Ex), no training (NoEx), 2000 IU/day vitamin D (VitD) and/or placebo (Pla) supplementation (giving four possible allocations: NoEx+VitD; NoEx+Pla; Ex+VitD; Ex+Pla). Vitamin D status, glycaemic control and exercise responses were measured pre- and post-intervention. A series of 2 x 2 ANOVAs failed to find any effect of supplementation or exercise on any of the measures except heart rate during low intensity exercise, and vitamin D status. Heart rate was significantly reduced (6%, p < 0.05) in the Ex+VitD group. Vitamin D status was significantly raised (28%, p < 0,05) in the supplementation groups (NoEx+VitD and Ex+VitD) at a time of year (August-November) when a seasonal decline was observed in the placebo groups (33%, p < 0.05). These findings indicate that vitamin D supplementation (2000 IU/day) may have an enhancing role alongside exercise in inducing cardiorespiratory adaptations to exercise training. Further investigations are required to confirm these findings and identify the mechanisms involved

Failure of oral tyrosine supplementation to improve exercise performance in the heat

PURPOSE Acute oral tyrosine administration has been associated with increased constant-load, submaximal exercise capacity in the heat. This study sought to determine whether self-paced exercise performance in the heat is enhanced with the same tyrosine dosage. METHODS After familiarization, seven male endurance-trained volunteers, unacclimated to exercise in the heat, performed two experimental trials in 30°C (60% relative humidity) in a crossover fashion separated by at least 7 d. Subjects ingested 150 mg·kg(-1) body mass tyrosine (TYR) or an isocaloric quantity of whey powder (PLA) in 500 mL of sugar-free flavored water in a randomized, double-blind fashion. Sixty minutes after drink ingestion, the subjects cycled for 60 min at 57% ± 4% peak oxygen uptake (VO2peak) and then performed a simulated cycling time trial requiring completion of an individualized target work quantity (393.1 ± 39.8 kJ). RESULTS The ratio of plasma tyrosine plus phenylalanine (tyrosine precursor) to amino acids competing for brain uptake (free-tryptophan, leucine, isoleucine, valine, methionine, threonine, and lysine) increased 2.5-fold from rest in TYR and remained elevated throughout exercise (P 0.05), RPE (P > 0.05), core temperature (P = 0.860), skin temperature (P = 0.822), and heart rate (P = 0.314) did not differ between trials. CONCLUSIONS These data indicate that acute tyrosine administration did not influence self-paced endurance exercise performance in the heat. Plasma tyrosine availability is apparently not a key determinant of fatigue processes under these conditions

Motivational State Does Not Affect All-Out Short Duration Exercise Performance

Introduction: The preferred motivational state (telic or paratelic), i.e., dominance, has been linked to the type of activity sports people participate in. As such, positive or negative performance may occur if there is a mismatch between the activity and the required state. This study set out to examine the effects of altering telic or paratelic motivational states and thus induce the ?misfit effect? in order to quantify the influences on emotions and performance during allout, short duration cycle performance. Methods: Based on paratelic dominance scale (PDS) scores participants completed the Wingate anaerobic test (WAT) on two separate occasions in their preferred and non-preferred motivational state. Special video display method was used to manipulate participants to their non-preferred motivational state and verified via the telic state measure (TSM) test prior to performing the Wingate test (WT). Changes in emotion and stress levels were recorded using the tension and effort stress inventory (TESI) along with heart rate variability (HRV) data obtained from electrocardiogram (ECG). Peak power (PP), mean power (MP) and fatigue index (FI) obtained from the WT were used to assess all-out athletic performance. Results: The main findings show that there was no link between dominant motivational state and anaerobic cycle performance (p>0.05) and that successful manipulation of motivational state (p<0.05) did not influence perceived levels or physiological levels of stress (p>0.05) and did not affect all-out, short duration cycle performance (p<0.05). Conclusion: As such, coaches, support staff and athletes do not have to worry about a particular state in regards to telic or paratelic in an acute time frame, as long as the athlete?s arousal levels and emotional conditions are optimal.publishersversionPeer reviewe

Zinc carnosine works with bovine colostrum in truncating heavy exercise–induced increase in gut permeability in healthy volunteers

Background: Heavy exercise causes gut symptoms and, in extreme cases, heat stroke that is due to the increased intestinal permeability of luminal toxins. Objective: We examined whether zinc carnosine (ZnC), a health-food product taken alone or in combination with bovine colostrum (a natural source of growth factors), would moderate such effects. Design: Eight volunteers completed a 4-arm, double-blind, placebo-controlled crossover protocol (14 d of placebo, ZnC, colostrum, or ZnC plus colostrum) before undertaking standardized exercise 2 and 14 d after the start of treatment. Changes in epithelial resistance, apoptosis signaling molecules, and tight junction (TJ) protein phosphorylation in response to a 2°C rise in body temperature were determined with the use of Caco-2 and HT29 intestinal cells. Results: Body temperature increased 2°C, and gut permeability (5-h urinary lactulose:rhamnose ratios) increased 3-fold after exercise (from 0.32 ± 0.016 baseline to 1.0 ± 0.017 at 14 d; P < 0.01). ZnC or colostrum truncated the rise by 70% after 14 d of treatment. The combination treatment gave an additional benefit, and truncated exercise induced increase at 2 d (30% reduction; P < 0.01). A 2°C temperature rise in in vitro studies caused the doubling of apoptosis and reduced epithelial resistance 3–4-fold. ZnC or colostrum truncated these effects (35–50%) with the greatest response seen with the combination treatment (all P < 0.01). Mechanisms of action included increasing heat shock protein 70 and truncating temperature-induced changes in B cell leukemia/lymphoma-2 associated X protein ? and B cell lymphoma 2. ZnC also increased total occludin and reduced phosphorylated tyrosine claudin, phosphorylated tyrosine occludin, and phosphorylated serine occludin, thereby enhancing the TJ formation and stabilization. Conclusion: ZnC, taken alone or with colostrum, increased epithelial resistance and the TJ structure and may have value for athletes and in the prevention of heat stroke in military personnel. This trial was registered at www.isrctn.com as ISRCTN51159138

The effects of bovine colostrum supplementation on in vivo immunity following prolonged exercise:A randomised controlled trial

Background?Bovine colostrum (COL) has been advocated as a nutritional countermeasure to exercise-induced immune dysfunction but there is a lack of research with clinically relevant in vivo measures.? AimTo investigate the effects of COL supplementation on in vivo immunity following prolonged exercise using experimental contact hypersensitivity (CHS) with the novel antigen Diphenylcyclopropenone (DPCP). MethodsIn a double-blind design, 31 men were randomly assigned to COL (20 g/day) or placebo (PLA) for 58 days. Participants ran for 2 h at 60% maximal aerobic capacity on day 28 and received a primary DPCP exposure (sensitisation) 20 min after. On day 56, participants received a low dose-series DPCP challenge to elicit recall of in vivo immune-specific memory (quantified by skinfold thickness 24 h and 48 h later). Analysis of the dose response curves allowed determination of the minimum dose required to elicit a positive response (i.e. sensitivity). ResultsThere was no difference in summed skinfold thickness responses between COL and PLA (p > 0.05). However, sensitivity of in vivo immune responsiveness was greater with COL at 24 h (p < 0.001) and 48 h (p < 0.05) with doses ~2-fold greater required to elicit a positive response in PLA.? ConclusionsCOL blunts the prolonged exercise-induced decrease in clinically relevant in vivo immune responsiveness to a novel antigen, which may be a mechanism for reduced illness reports observed in previous studies. These findings also suggest that CHS sensitivity is highly relevant to host defence and in vivo protection against infection.publishersversionPeer reviewe