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Anni Heikkinen, Antti Alaranta, Ilkka Helenius and Tommi Vasankari

The aim of this study was to evaluate the frequency of dietary supplement (DS) use among elite Finnish athletes in 2002 and 2009. In 2009, the authors also wanted to examine the reasons for athletes’ DS use, whether athletes feel they have experienced benefits from their supplement use, and whether athletes had had an opportunity to consult dietary specialists. Cross-sectional studies were conducted in 2002 and 2009 among Finnish Olympic athletes. Data were collected using semistructured questionnaires, mainly in national team camps. The study population in 2002 was 446 athletes, and in 2009 it was 372. The number of DS users was high in both study years (81% in 2002 and 73% in 2009). Vitamin D consumption was low in both 2002 and 2009 (0.7% and 2.0%, respectively). An increase was found in consumption of omega-3 fatty acids between study years (11% in 2002 and 19% in 2009; p = .002), and their regular use nearly doubled (8% and 15%, p = .002). For vitamin and mineral users, the main reason for DS use was to prevent nutritional deficiencies, and for nutritional supplement users the main reason was recovery from exercise. Only 27% of all athletes and 30% of DS users had an opportunity to consult dietary specialists in 2009. This survey shows that supplementation rates among elite Finnish athletes are high and there may be over- and underuse of some micronutrient supplements. There is a need for professional nutritional counseling among national elite athletes.

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Jonathan M. Oliver, Dustin P. Joubert, Steven E. Martin and Stephen F. Crouse

Purpose:

To determine the effects of creatine supplementation on blood lactate during incremental cycling exercise.

Methods:

Thirteen male subjects (M ± SD 23 ± 2 yr, 178.0 ± 8.1 cm, 86.3 ± 16.0 kg, 24% ± 9% body fat) performed a maximal, incremental cycling test to exhaustion before (Pre) and after (Post) 6 d of creatine supplementation (4 doses/d of 5 g creatine + 15 g glucose). Blood lactate was measured at the end of each exercise stage during the protocol, and the lactate threshold was determined as the stage before achieving 4 mmol/L. Lactate concentrations during the incremental test were analyzed using a 2 (condition) × 6 (exercise stage) repeated-measures ANOVA. Differences in power at lactate threshold, power at exhaustion, and total exercise time were determined by paired t tests and are presented as M ± SD.

Results:

Lactate concentrations were reduced during exercise after supplementation, demonstrating a significant condition effect (p = .041). There was a tendency for increased power at the lactate threshold (Pre 128 ± 45 W, Post 143 ± 26 W; p = .11). Total time to fatigue approached significant increases (Pre 22.6 ± 3.2 min, Post 23.3 ± 3.3 min; p = .056), as did maximal power output (Pre 212.5 ± 32.5 W, Post 220 ± 34.6 W; p = .082).

Conclusions:

Our findings demonstrate that creatine supplementation decreases lactate during incremental cycling exercise and tends to raise lactate threshold. Therefore, creatine supplementation could potentially benefit endurance athletes.

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Hans Braun, Karsten Koehler, Hans Geyer, Jens Kleinert, Joachim Mester and Wilhelm Schänzer

Little is known about the prevalence and motives of supplement use among elite young athletes who compete on national and international levels. Therefore, the current survey was performed to assess information regarding the past and present use of dietary supplements among 164 elite young athletes (16.6 ± 3.0 years of age). A 5-page questionnaire was designed to assess their past and present (last 4 weeks) use of vitamins, minerals, carbohydrate, protein, and fat supplements; sport drinks; and other ergogenic aids. Furthermore, information about motives, sources of advice, supplement sources, and supplement contamination was assessed. Eighty percent of all athletes reported using at least 1 supplement, and the prevalence of use was significantly higher in older athletes (p < .05). Among supplement users, minerals, vitamins, sport drinks, energy drinks, and carbohydrates were most frequently consumed. Only a minority of the athletes declared that they used protein/amino acids, creatine, or other ergogenic aids. Major motives for supplement use were health related, whereas performance enhancement and recommendations by others were less frequently reported. Supplements were mainly obtained from parents or by athletes themselves and were mostly purchased in pharmacies, supermarkets, and health-food stores. Among all athletes, only 36% were aware of the problem of supplement contamination. The survey shows that supplement use is common and widespread among German elite young athletes. This stands in strong contrast to recommendations by leading sport organizations against supplement use by underage athletes.

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Dariush Sheikholeslami-Vatani, Slahadin Ahmadi and Hassan Faraji

protective effects of omega-3 and BCAA against oxidative stress ( D’Antona et al., 2010 ; Yu et al., 2009 ), DNA damage ( Carvalho-Silva et al., 2017 ; Ra et al., 2013 ), and proinflammatory cytokines ( Tayyebi-Khosroshahi et al., 2012 ), it is possible that omega-3 and BCAA supplementation attenuates

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Rebekah D. Alcock, Gregory C. Shaw and Louise M. Burke

the collagen content and mechanical properties of an engineered ligament exposed to a stretch stimulus ( Shaw et al., 2017 ). Meanwhile, other investigations have demonstrated the benefit of hydrolyzed collagen supplementation in a range of collagen-containing tissues ( Daneault et al., 2017 ; Oesser

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Michael J. Ormsbee, Brandon D. Willingham, Tasha Marchant, Teresa L. Binkley, Bonny L. Specker and Matthew D. Vukovich

<1.3 g·kg −1 ·day −1 ( Cermak et al., 2012 ; Morton et al., 2017 ). When individuals who are unaccustomed to resistance exercise begin a new training program, the influence of protein supplementation may augment their physiological responses, especially over the short term ( Gontzea et al., 1975

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Carl M. Maresh, Lawrence E. Armstrong, Jay R. Hoffman, Daniel R. Hannon, Catherine L. V. Gabaree, Michael F. Bergeron, Michael J. Whittlesey and Michael R. Deschenes

In the present study, the effects of an increased daily dose of a dietary supplement (ATP-E, 0.2 g · kg1 · day1) on Wingate test performance were examined in 12 men (21 ± 1.6 years) prior to and following 14 days of supplement and placebo ingestion. A double-blind and counterbalanced design was used. Results revealed higher (p < .007) preexercise blood ATP (95.4 ± 10.5 μmol · dl1) for the entire group following 14 days of ATP-E ingestion compared to placebo measures (87.6 ± 10.9 μmol · dl1). Mean power (667 ± 73 W) was higher (p < .008) after 14 days of ATP-E ingestion versus placebo (619 ± 67 W). Peak plasma lactate was lower (p < .07) after 14 days of ATP-E ingestion (14.9 ± 2.8 mmol · L1) compared to placebo (16.3 ± 1.6 mmol · L1). These data suggested that the improvement in 30-s Wingate test performance in this group may be related to the increased dose of ATP-E.

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Kirsty A. Fairbairn, Ingrid J.M. Ceelen, C. Murray Skeaff, Claire M. Cameron and Tracy L. Perry

Vitamin D is a secosteroid hormone that may directly act on skeletal muscle ( Ceglia, 2008 ; Hamilton, 2010 ). Muscle function is impaired in severe vitamin D deficiency like rickets and osteomalacia ( Wharton & Bishop, 2003 ), and supplementation of between 420 and 8,570 IU/day for 3–6 months in

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Mark Messina, Heidi Lynch, Jared M. Dickinson and Katharine E. Reed

; Wilkinson et al., 2013 ). Although acute studies evaluating MPS may provide valuable insight, MPS following protein supplementation and resistance exercise may last for at least 24 hr ( Burd et al., 2011 ). Thus, it is important to determine how protein source affects changes in strength and lean tissue

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Kristin Wiens, Kelly Anne Erdman, Megan Stadnyk and Jill A. Parnell

Purpose:

To evaluate dietary supplement use in young Canadian athletes, their motivation for consuming supplements, and their sources of information.

Methods:

A questionnaire tested for content validity and reliability was administered to 567 athletes between the ages of 11 and 25 years from the Canadian athletic community in face-to-face meetings. Demographics and sport variables were analyzed using descriptive statistics. Fisher’s exact tests were used to examine dietary supplementation patterns and sources of information regarding dietary supplement use between categories of gender, age, sport type, and competition level.

Results:

Ninety-eight percent of athletes were taking at least one dietary supplement. Males were more likely to consume protein powder, energy drinks, recovery drinks, branched chain amino acids, beta-alanine, and glutamine (p < .01); supplements typically associated with increased muscle mass. Athletes 11–17 years old focused on vitamin and mineral supplements; whereas, athletes 18–25 years old focused on purported ergogenic supplements. Strength training athletes were more likely to consume creatine, glutamine, and protein powders (p < .02). Reasons for supplement use included to stay healthy, increase energy, immune system, recovery, and overall performance. Primary sources of information were family and friends, coaches, and athletic trainers; with 48% of athletes having met with a dietitian. Preferred means of education included individual consultations, presentations, and the internet.

Conclusions:

The majority of young athletes are using dietary supplements with the belief they will improve performance and health; however, may not always have reliable information. Educational programs using individual consultations and electronic media are recommended for this demographic.