The Effects of Caffeine and Pre-Workout Multi-Ingredient Performance 1 Supplement on Reactive Agility and Countermovement Jump Height

Background: The purpose of this investigation was to examine the acute effects of a 21 commercially available multi-ingredient performance supplement (MIPS) in comparison to 22 caffeine, on reactive agility and jump height, in recreationally-trained handball male players. 23 Methods: The study followed a randomized double-blind, crossover design. Twenty-four 24 individuals were treated with placebo, caffeine or multi-ingredient performance supplement 25 (MIPS). Dosage of caffeine in caffeine supplement and MIPS contain the same amounts of 26 caffeine for each subject (5 mg/kg). All subjects attended a familiarization session 1 week 27 before testing. Participants underwent reactive agility test (Y-test: 1-1-2 test) on three separate 28 days with 72 h apart between test days. Just after accomplishing of each repetition of reactive 29 agility tests participants were asked to perform countermovement jump (CMJ; 2 repetitions 30 separated by one minute break) to establish the average height of jump, that is directly related 31 to lower body power. To assess the significance of differences between the groups studied, 32 Friedmann ANOVA test was used, the chi-square value (χ2) calculated and the p value of 33 statistical significance estimated. Results: The research indicated significant inter-group differences in 1-1-2 agility test (p=0.04). The time was significantly shorter for MIPS supplement group in comparison to placebo (- 36 3.4%; p=0.02) and to caffeine (-2.8%; p=0.004) group. Significant improvements (p<0.01) 37 were observed in jump height for MIPS supplement group in comparison to placebo (+5.2%; 38 p=0.001) and caffeine (+5.1%; p=0.001) groups, but not in caffeine to placebo comparison 39 (p=0.84). Conclusions: The results of these study may contribute to the assessment of the usefulness of 41 multi-ingredient performance type supplementation in comparison to the ingestion of identical 42 amounts of caffeine only in enhancing reactive agility and jump performance.

Agility is a skill required for most field sports. Sheppard and Young (1) have defined 48 reactive agility as a rapid whole body movement with change of velocity or direction in 49 response to a stimulus. In many sport disciplines, changes of speed or rapid and decisive 50 changes of direction can result in a break, a score or a shift in the momentum of the game (2). 51 It should be noted that successful performance in team sports stresses not only physiological 52 systems but also imposes a high degree of technical and cognitive demands (3). Therefore 53 methods effecting in improving psychomotor performance is gaining importance among 54 players, coaches and sport scientists. 55 Many athletes believe supplementation with multi-ingredient performance supplement 56 (MIPS) prior to training will result in greater focus, shorter reaction time, and increased power 57 (4,5). Therefore, the beneficial properties of such products for team sport athletes may not be 58 effective in increasing endurance or/and strength performance per se but rather in improving 59 decision-making and perceptual skills. As was proven in the studies by Kaczka  peripheral and central mechanisms (7). Research indicate that decision-making and perceptual 64 skills may be improved by caffeine ingestion however results remain unclear. Lorino et al. (8) 65 found no improvement in total time (TT) to complete a proagility run following ingestion of 6 66 mg/kg body mass (BM) of caffeine (1 h before exercise). In contrast, Stuart et al. (9) reported that caffeine ingestion (6 mg/kg BM) resulted in a 2,2% improvement in mean performance 68 across three separate reactive agility sprints in zig-zag manner. It is important that both of these 69 studies used preplanned movement tests, which do not require to "read and react" -thus 70 perceptual component of reactive agility has been eliminated. To the current knowledge of 71 authors only one study showed improved reactive agility in team-sport athletes after 6 mg/kg 72 caffeine ingestion 60 min prior to exercise (10). 73 It is believed that ingredients found in many MIPS such as caffeine, beta-alanine, 74 citrulline and plant ingredients which target different physiological mechanisms may elicit 75 synergistic effect and in turn improve athletic performance (4; 11). For example hordenine, a 76 constituent of barley and beer, has approximately identical ligand efficacy as dopamine (76%) 77 (12). Hordenine is also found in Citrus aurantium which has been shown to have influence on 78 adrenergic receptors by stimulating the release of noradrenaline (norepinephrine -NE) (13,14). 79 Therefore, it could be hypothesized that with caffeine and other sympathomimetic ingredients dopaminergic and catecholaminergic effect may be also enhanced by tyrosine, which is found 82 in many pre-workouts. Norepinephrine, along with dopamine, has come to be recognized to 83 play significant role in focus and alertness. This is perhaps not surprising given the location and 84 distribution of NE neurons throughout the brain (15 (4,12,16,17,18,19). 95 Therefore, the purpose of this investigation was to examine the acute effects of a 96 commercially available multi-ingredient pre-workout performance supplement in comparison 97 to caffeine, on reactive agility and on jump height, in recreationally-trained handball male 98 players. It was hypothesized that the supplement would improve reactive agility decision-99 making skills relative to placebo and caffeine due to the presence of biologically-active 100 ingredients, that may enhance cognitive performance, as well as preventing the decrease in 1975 Helsinki Declaration. The study followed a randomized double-blind, crossover design.

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All subjects attended a familiarization session one week before testing. During the 113 familiarization session the participants were shown and explained the planned tests as well as 114 their order on one day and their order during the entire experiment. They were also instructed 115 not to consume caffeine containing products 24 hours before testing, to reduce the effect of 116 caffeine tolerance. The subjects were asked to refrain from heavy exercise and alcohol consumption during period of the experiment. In addition, subjects were instructed not to eat or 118 drink for three hours prior to each trial. Subjects underwent reactive agility test on three separate 119 days with 72 h apart between test days. Just after accomplishing of each repetition of reactive 120 agility tests participants were asked to perform countermovement jump (CMJ; two repetitions 121 separated by one minute break) to establish the average height of jump, that is directly related 122 to lower body power.   instructed not to try to predict which exit gate they would be required to sprint through; to 165 ensure that this did not occur, the investigator visually monitored technique and compared 166 reactive performance times to planned sprint times. Participants had completed the test until test 1-1-2 scheme is shown in Figure 1.        (25,29). Giving the same dose to someone who already 250 is well-rested and highly aroused may degrade rather than improve performance because in this 251 case, caffeine produces a state of over-arousal, which according to the Yerkes-Dodson law, will 252 degrade cognition (29,30,31). Research has shown that better performance can be 253 distinguished from lower skilled athletes by the ability to quickly and accurately react to which could enhance cognitive function (33,34).

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Relatively high values of CMJ height, presented in this study, may be due to the used 270 modality, that included arm swing and the depth of the countermovement directly before the 271 jump (20). As other authors stated -5 cm increase in countermovement depth significantly 272 influences jump performance (35). Higher jump and joint angular velocities were also observed 273 wen the knee flexion range increased from 70° to 90° (36).
There are many studies (37,38)  ergogenic aid, such as oral caffeine administration, is more apparent in highly trained athletes.

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Moreover the effect tends to be stronger for exercises involving large muscle groups (41).  Limitations of the study 296 Given the scarcity of research on the MIPS blend composition, more research is 297 warranted to gain a better understanding of their effects on sport performance and reactive 298 agility, the more that the presence of additional biologically-active ingredients in the multi-  as well as between MIPS and CAF groups (**p=0.001), but not CAF and PL groups (p=0.84).