View clinical trials related to Exercise Performance.
Filter by:Dietary nitrate, L-citrulline, epicatechin, vitamin C and glutathione have the potential to improve nitric oxide (NO) bioavailability, in humans, by influencing both the nitrate-nitrite-NO and NO synthase-dependent pathways, and the storage of NO. The study is designed to assess the efficacy of a newly developed product containing a mixture of these compounds. Specifically, the study will assess if the product is capable of increasing NO bioavailability and if this results in positive effects on exercise economy and intermittent exercise performance. These outcome measures have been chosen because they have previously been positively impacted by an increase in NO bioavailability.
Both acute ingestion (1-3 h) and chronic supplementation (3-30 days) with dietary nitrate has been shown to increase nitric oxide activity and, in some studies, to improve exercise economy, exercise tolerance, and endurance exercise performance. In addition, more recent evidence suggests that dietary nitrate has the potential to enhance team-sport-specific high-intensity intermittent exercise performance. Indeed, chronic dietary nitrate supplementation (2-6 days) has been reported to increase the distance covered before exhaustion during the Yo-Yo intermittent recovery level 1 test, a well-established and ecologically valid test widely used to mimic the high-intensity running bouts of soccer match-play. However, while these findings suggest that nitrate may be an effective ergogenic aid for team-sport players when consumed daily, it is currently unclear if the improvement in team-sport specific intermittent exercise performance can be achieved following a single bolus of dietary nitrate. Given the increasing interest and use of dietary nitrate as an ergogenic aid by team-sport players, establishing the shortest period of supplementation required to elicit an ergogenic effect is important in order to guide athletes on optimal supplementation strategies. Given that a single bolus of dietary nitrate has previously been shown to improve exercise tolerance and endurance exercise performance, and an improved Yo-Yo IR1 performance has been observed after chronic nitrate supplementation, the investigator hypothesizes that acute (2 h) and short-term (4 days) nitrate supplementation will significantly elevate nitric oxide activity (measured as an increase in plasma nitrite concentration and skeletal muscle nitrate concentration) and improve performance during the Yo-Yo IR1 test (measured as an increased in distance covered (m) during the test at the point of volitional exhaustion) to a similar extent, when compared to a placebo.
Dietary nitrate (NO3-) supplementation has been shown to improve skeletal muscle contractility and fatigue resistance, particularly in fast-twitch (type II) muscle fibers. Furthermore, NO3- supplementation has been shown to speed reaction time. Taken together, these findings suggest that NO3- ingestion may be ergogenic during all-out sprint running and reactive agility tasks. Moreover, increasing muscle force production at high contraction speeds would be expected to translate into improved muscle power and, subsequently, improved performance in very explosive forms of exercise, such as vertical jumping. Therefore, the purpose of this investigation is to assess the effect of short term (5 days) NO3- supplementation on linear running sprint performance, reactive agility and vertical jump performance in a rested and fatigued state.
The goals of the present study are to evaluate whether the most common, and effective, treatment for acute mountain sickness (AMS), acetazolamide (AZ), has a negative, positive, or no influence on exercise performance, cognitive performance, or manual dexterity in young healthy subjects during simulated altitude exposure. AMS represents a serious challenge to the health and performance of the Warfighter who may need to rapidly deploy to high altitude. However, there have been concerns that AZ might alter or impair endurance exercise performance, and possibly fine motor skills. These would represent major limitations to the use of this drug in a Warfighter who has a specific timeframe in which to accomplish mission tasks. In the present project, we will use exposure to simulated altitude in the USARIEM hypobaric chamber to quantify the impact, if any, of AZ on endurance exercise performance following rapid ascent to 3500 meters (m) in unacclimatized lowlander volunteers. The study will be conducted using a randomized, single-blind, placebo-controlled crossover study design. Ten male and female volunteers will complete one orientation day, one VO2peak day, three days of familiarization testing at sea level (SL), then two rounds of experimental testing. Each round of experimental testing consists of six days including four days to establish baseline euhydration, followed by a 30 hour (hr) exposure to 3500 m. Volunteers will have a two week break between experimental testing rounds for washout of any effects of altitude acclimation. During one experimental round, volunteers will take two doses of AZ each day (Phase 1: 250 mg/dose,500 mg/day, Phase 2: 125 mg/dose, 250 mg/day) starting 48 hr prior to their altitude exposure and continuing for the 30 hr stay at high altitude. During the other experimental condition, volunteers will be given a placebo at the same time points as the doses of AZ. Prior to altitude exposure, AMS will be evaluated and volunteers will then ascend to a simulated altitude of 3500 m, where they will remain for 30 hr. Volunteers will rest at altitude for an hr, after which they will complete an AMS questionnaire, resting ventilation measurements, provide a blood sample and complete cognitive and finger dexterity testing. Subjects will then perform 15 minutes (min) of steady state (SS) treadmill exercise at 40-45% of SL VO2peak and a 2 mile treadmill time trial (TT). Volunteers will stay overnight in the hypobaric chamber with research staff supervision. The following morning, metabolic and blood measurements will again be completed, after which volunteers will perform the exercise testing for a second time. Cognitive and finger dexterity testing will be performed before volunteers return to sea level (i.e., "descend" from the simulated altitude). The results of the proposed study will, for the first time, provide quantitative evidence regarding whether AZ treatment impairs endurance exercise performance in the context of a Warfighter-relevant endurance exercise task.
This research study evaluates the feasibility and appropriateness of potatoes as an ergogenic aid in comparison to the currently promoted sports gels during a cycling challenge and time trial. Using a crossover design, trained cyclists will complete three separate cycling challenges and subsequent time trials in which they will consume either potatoes, commercially available sports gels, or water only.
In this study, the effect of citrus extract on exercise performance will be investigated. The study consists of three groups: one group will receive a high dose citrus extract, one group will receive a low dose citrus extract and the last group will receive a placebo. After four and eight weeks the effects on performance are measured through a Wingate cycling test. It is expected that exercise performance will increase in the citrus extract groups, compared to the placebo group.
Bovine colostrum is the milk produced by cows immediately after calving. It contains high levels of proteins that improve immune protection and may act to prevent colds. During intense training, athletes often have compromised immune function. This may be especially true in club-level rugby players who abruptly start high intensity training in the spring in preparation for their competitive season. Our study will assess the effects of supplementing these players with bovine colostrum during this intense training. Thirty-six players will be recruited; half will consume colostrum during the 8 weeks of early-season training and half soy protein. The investigators predict the bovine colostrum supplement will improve health during the training and increase fitness levels.
Hyperbaric oxygen has previously been tested as a possible means for pre-conditioning to enhance exercise performance. This study is designed to examine the effects of exercising in a hyperbaric chamber for improving fitness when combined with high-intensity training.
In humans, the primary means of cooling the body during exercise is through the evaporation of sweat from the skin surface. Clothing represents a layer of insulation that hinders the evaporation of sweat from the surface of the skin. It follows that clothing that imposes the least amount of resistance to evaporative heat loss may prove beneficial to the thermoregulatory, physiological and perceptual response to exercise, particularly in elite endurance-trained athletes. Thus, the purpose on this study is to examine the influence of wearing a sportswear garment made of a fabric (100% nylon) with superior evaporative characteristics on detailed thermoregulatory, cardiorespiratory, metabolic and perceptual responses to maximal exercise testing at normal room temperature and relatively humidity in a group of 25 endurance-trained cyclists and triathletes aged 20-60 years. It is hypothesized that wearing a garment made of 100% nylon will improve exercise performance (e.g., exercise endurance time) and that this improvement will reflect improvements in thermoregulatory, cardiorespiratory, metabolic and perceptual responses to exercise. Athletes will be recruited via contact with coaches of the McGill University Cycling and Triathlon teams as well as through contact with coaches of competitive cycling and triathlon teams/training groups in the Montreal and surrounding area. Initial contact will consist of a thorough explanation of the study procedures and pre-screening for the inclusion/exclusion criteria prior to study consent by the Principal Investigator and/or his delegate, either in person or by telephone or email. Eligible participants will visit McGill's Clinical Exercise & Respiratory Physiology Laboratory on 3 separate occasions over a period of 10-14 days. Visit 1 will include a maximal incremental bicycle exercise test for familiarization purposes and to determine maximal power output (MPO). Visits 2 and 3 will include a constant-power-output bicycle exercise test at 85% MPO under one of two conditions, in randomized order: (1) while wearing a garment made of 100% polyester, i.e., placebo; and (2) while wearing a garment made of 100% nylon, i.e., cooling fabric. At rest and during exercise at visits 2 and 3, detailed assessments of core body temperature will be made using a temperature sensor placed into the esophagus, while skin temperature and other physiological and perceptual parameters will be measured using standard techniques.
The purpose of this study is to examine if the ingestion of a standard dose of sildenafil enhances the athletic performance of competitive athletes when exercising in a high pollutant environment verses a low air pollutant environment.