Effects of a nutritional supplement on maximum strength in resistance trained males

Konstantaki, Maria and Eltahnaway, S. (2014) Effects of a nutritional supplement on maximum strength in resistance trained males. In: 19th Annual Congress of the European College of Sports Science, 2 - 5 July, 2014, Amsterdam, The Netherlands.

Konstantaki, M & Eltahnaway 2014 ECSS Amsterdam Effects of a nutritional supplement on maximum strength in resistance trained males.pdf
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Introduction: Jack3d is a powder based nutritional supplement that according to its manufacturers it can boost energy levels, increase endurance, improve focus and enhance the ability to lift more weight. The supplement is designed for those engaging in regular re-sistance training. However there have not been any published research studies investigating the supplement’s effectiveness in athletic or other populations. Therefore, the aim of this study was to investigate the effects of Jack3d on mental and physical strength. Methods: Sixteen resistance trained males (mean ± s; age: 23.88 ± 3.73 years, body mass: 74.06 ± 7.73 kg, stature: 174.63 ± 5.0 cm) signed an informed consent and participated in the study. Participants first performed a 1RM bench press test to establish upper body muscle strength and were randomly assigned to one of two groups; experimental group who would consume the supplement (Jack3d) and control group who would consume a placebo drink (PLA). Six days later, Jack3d consumed a drink containing 5.5 g of the Jack3d supplement diluted in 230 ml of water, whereas PLA consumed the same quantity of diluted peach juice. Bot h groups ingested the drink 40 minutes prior to testing to allow for gastric emptying. Following a standardised warm up, participants performed a re-test 1RM bench press test. A self reported questionnaire was used to assess states of mental strength under the two c onditions. Results Following consumption of Jack3d there was a 1.90 ± 0.03% improvement in the 1RM (82.18 ± 15.08 kg and 83.75 ± 14.07 kg, for first and second lift, respectively, P=0.04). There was no significant improvement (0.3 ± 0.03%) in PLA (85.31 ± 9.0 kg and 85.62 ± 9.13 kg, P=0.11). Participants in the Jack3d group reported increased alertness, competitive drive and aggressive feelings. Discussion These results indicate that the amount of Jack3d consumed in our trial is adequate to increase maximum strength of resistance trained males. The improvements were small however this might be due to the trained subjects we used in the study. Jack3d contains a number of ingredients such as creatine, caffeine, beta-alanine, arginine and dimethylamylamine (DMAA) that have been shown to improve muscular strength, increase alertness, buffer waste products or mobilise fatty acids. The exact mechanism of how Jack3d induced changes in muscular strength calls for further investigation. However, the ingredient DMAA is currently a listed drug in New Zealand and is also a banned substance on the World Anti-Doping Agency list (WADA, 2012). This study aims to raise awareness among the athletic populations regarding the short term effects of Jack3d use, but also the possible implications for yielding a positive drugs test.

Item Type: Conference or Workshop Item (Paper)
Depositing User: ULCC Admin
Date Deposited: 28 Jan 2016 13:56
Last Modified: 10 Jan 2018 10:08
URI: https://bnu.repository.guildhe.ac.uk/id/eprint/9518

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