Official Journal of the American College of Sports Medicine Vol. 52 No. 5 Supplement S521 Abstracts were prepared by the authors and printed as submitted. FRIDAY, MAY 29, 2020 E-06 Thematic Poster - Buffers Friday, May 29, 2020, 9:30 AM - 11:30 AM Room: CC-2000 2445 Chair: Bryan Saunders. University of Sao Paulo, Sao Paulo, Brazil. (No relevant relationships reported) 2446 Board #1 May 29 9:30 AM - 11:30 AM The Efficacy Of Topical Sodium Bicarbonate Application On Blood Buffering Capacity And Exercise Tolerance Rebecca L. Cross 1 , Alannah McKay 2 , Peter Peeling 2 , Martyn Binnie 3 , Paul Goods 2 , Marc Sim 4 , Jason Siegler, FACSM 1 . 1 Western Sydney University, Penrith, Australia. 2 University of Western Australia, Crawley, Australia. 3 Western Australian Institute of Sport, Mt Claremont, Australia. 4 Edith Cowan University, Western Australia, Australia. (Sponsor: Jason Siegler, FACSM) Email: r.cross@westernsydney.edu.au Reported Relationships: R.L. Cross: Industry contracted research; AMP Human. The ingestion of sodium bicarbonate (NaHCO3) to improve short duration, high intensity exercise performance is widely practiced in elite athletics, rowing and track cycling. However, gastrointestinal (GI) distress is a common side-efect of NaHCO3 supplementation which has been suggested to mitigate the performance- enhancing potential of NaHCO3 supplementation. With this in mind, a method of NaHCO3 administration that bypasses the GI tract may be a favourable alternative to oral supplementation. PURPOSE: The purpose of this study was to compare the blood bufering profle and exercise responses between a commercially available topical NaHCO 3 lotion and a typical, orally ingested amount (0.3 g/kg body weight (BW) NaHCO 3 ). METHODS: 10 recreationally active participants completed two experimental trials (randomised and counterbalanced); oral NaHCO 3 (0.3g/kg BW + placebo lotion) or topical NaHCO 3 lotion (0.9036 g/kg BW + oral placebo) applied or ingested 90 min prior to a cycling task to exhaustion (repeat 30 s cycling eforts at 120% peak power output with 30 s rest). Capillary blood was collected and analysed for pH, bicarbonate (HCO 3 - ) and lactate every 10 min throughout the 90 min loading period and post-exercise at 5, 10 and 15 min. RESULTS: pH and [HCO 3 - ] were signifcantly elevated from baseline after 10 min in the oral NaHCO 3 condition and throughout recovery compared to the topical lotion (p<0.001). No diferences in cycling performance (e.g. cumulative time) were observed between the oral NaHCO 3 condition (363±80s;) and topical NaHCO 3 lotion condition (349 ± 119 s; p=0.697). CONCLUSION: Topical NaHCO 3 lotion (0.9036 g/kg BW) did not signifcantly increase blood bufering capacity, suggesting that concentrations used in the present study have limited transdermal absorption capacity into the wider circulation. 2447 Board #2 May 29 9:30 AM - 11:30 AM Effects Of Chronic Bicarbonate Supplementation On Kicking Performance In Highly Trained Taekwondo Athletes Gloria Velasquez 1 , Oscar Cajbon 2 , Manuel Alvarez 2 , Tanuj Wadhi 3 , Luis del Valle 1 . 1 Confederación Deportiva Autónoma de Guatemala, CDAG/Comité Olímpico Guatemalteco, COG, Guatemala, Guatemala. 2 Federación Nacional de Taekwondo de Guatemala, Guatemala, Guatemala. 3 University of Tampa, Tampa, FL. Email: gloriavelazquez@yahoo.com (No relevant relationships reported) It has previously been observed that a competitive full-contact Taekwondo combat simulation produced progressively increasing blood lactate concentrations up to 12.3 mmol·L⁻¹ by the third round, resulting in an increment of hydrogen ions (H + ) which causes fatigue and performance impairment. Chronic bicarbonate (BI) ingestion has been shown to act as an extracellular bufer agent of H + , improving performance during intense exercise. PURPOSE: Determine the efect of chronic BI supplementation on kicking performance in highly trained athletes during a taekwondo intermittent kick feld test (TIKT). METHODS: A single-blinded, randomized, crossover study was conducted over 6 weeks on 14 athletes from the Guatemalan national taekwondo team (ages:17.2±3 yrs). Athletes performed TIKT in pairs, with heart rate monitors and electronic chest protectors. During TIKT, athletes strived for the maximal number of kicks (NK), alternating with their partner for 10s, interspersed with 10s of active recovery, all during 4 rounds of 2 min x 1 min of rest. Five days before the trials, athletes took 0.3g/kg of either BI or placebo (PL) (maltodextrin + NaCl) divided in 3 doses taken 90, 60 and 30 min before a training session and before TIKT. RESULTS: For kicking performance, there was a signifcant main condition efect (p ≤ 0.05) in which BI increased NK compared to control (CL) (estimated diferences (ED): 16.1). The same was true for the theoretical score, BI vs CL (ED: 32). Although there was a greater NK with BI, there were no signifcant diferences (p ≥ 0.05) between BI vs PL (ED: 7.5). There was a main condition efect (p ≤ 0.05) in which BI and PL produced lower mean heart rate compared to CL (BI, ED: 10.9 and PL, ED: 9.8). Post TIKT lactate values were similar (p ≥ 0.05) in both BI and PL. There were no signifcant diferences between groups (p ≥ 0.05) in kicking efectiveness (combat score divided by theoretical score times 100). CONCLUSION: Our data indicate that kicking performance was enhanced in highly trained taekwondo athletes when chronically supplementing BI by increasing number of kicks but not efectiveness during a TIKT. Furthermore, from a practical point, while not signifcant, the improvement in other variables with BI (especially the combat score), could potentially be the diference between standing on the podium or not. 2448 Board #3 May 29 9:30 AM - 11:30 AM Changes In Cognition During A 24-h Simulated Military Operation. Role Of Classical Monocytes And Beta- alanine. Adam J. Wells 1 , Alyssa N. Varanoske 1 , Nicholas A. Coker 1 , Gregory J. Kozlowski 1 , Yftach Gepner 2 , Cheyanne L. Frosti 1 , David Bofey 1 , Idan Harat 1 , Jay R. Hofman, FACSM 3 . 1 University of Central Florida, Orlando, FL. 2 Tel Aviv University, Tel Aviv, Israel. 3 Ariel University, Ariel, Israel. (Sponsor: Jay Hofman, FACSM) (No relevant relationships reported) Cognitive dysfunction during sustained military operations (SUSOP’s) may be related to the recruitment and infltration of classical monocytes into the brain. Beta-alanine (BA) supplementation may attenuate cognitive dysfunction and improve resilience to stress exposure, which may be relevant during a SUSOP. PURPOSE: To examine the efect of BA on serum monocyte chemoattractant protein-1 (MCP1), C-C chemokine receptor 2 (CCR2), macrophage-1-antigen (CD11b) and cognition (COG), and to examine the relationships between these variables during a SUSOP. METHODS: Nineteen recreationally active men ingested 12g·day -1 BA (n = 10) or placebo (PL; n = 9) for 14-days prior to completing a simulated 24-h SUSOP. MCP1 was assessed via multiplex assay. Classical monocyte CCR2 and CD11b expression were assessed via fow cytometry. Throughput (TP) scores were extracted from seven cognitive subtests administered via Automated Neuropsychological Assessment Metric (ANAM) software. The relative weight of each ANAM subtest was determined by dividing its outer weight by the standard deviation of all TP scores for that subtest. TP scores were multiplied by their relative weights, and the values summed to provide a value for COG. Assessments occurred at baseline (0H), 12-hours (12H), 18-hours (18H) and 24-hours (24H). A two-way mixed ANOVA was used to assess diferences between BA and PL. The statistical signifcance of pathway (β) coefcients derived from partial least squares structural equation modeling were used to evaluate relationships between MCP1, CCR2, CD11b and COG. RESULTS: MCP1 was signifcantly greater at 12H, 18H and 24H relative to 0H (p’s < 0.001). CCR2 expression was signifcantly lower at 12H (p = 0.031), 18H and 24H (p’s < 0.001), while CD11b expression was signifcantly greater at 12H (p = 0.039) and 24H (p = 0.003) relative to 0H. COG was signifcantly lower at 18H and 24H compared to 0H and 12H (p’s ≤ 0.001). No signifcant diferences were noted between BA and PL for any variable (p’s > 0.05). MCP1 had a direct negative relationship with cognition (β = -0.395, p = 0.002). CCR2 and CD11b were not directly related to cognition (p’s > 0.50). CONCLUSIONS: Greater serum MCP1 concentrations were associated with increased cognitive dysfunction during the SUSOP. BA did not afect MCP1, CCR2, CD11b or COG compared to placebo. 2449 Board #4 May 29 9:30 AM - 11:30 AM Effect Of Beta-alanine Supplementation On Transporters Gene Expression And Long Distance Runner Performance. Gabriel S. Franco, Bruno A. F. de Oliveira, Flávia C. Ferreira, Natalia Y. Noronha, Ana Paula Pinto, Camila F. C. Brandao, Carla B. Nonino. University of São Paulo, Ribeirão Preto, Brazil. Email: gabriel_franco85@hotmail.com (No relevant relationships reported) Purpose: To evaluate the efect of beta-alanine supplementation in carnosine transporters gene expression (TauT and PAT1) and physical performance in athletes (long-distance runners). Methods: This double-blind randomized study enrolled sixteen males athletes (37 ± 8 years) divided into two groups: Placebo group (PLA), received starch (6 capsules/day) and Beta Alanine group (BA), received beta-alanine