Topical Sodium Bicarbonate: No Improvement in Blood Buffering Capacity or Exercise Performance

2020 ◽  
Vol 15 (7) ◽  
pp. 1005-1011
Author(s):  
Alannah K.A. McKay ◽  
Peter Peeling ◽  
Martyn J. Binnie ◽  
Paul S.R. Goods ◽  
Marc Sim ◽  
...  

Purpose: To assess the efficacy of a topical sodium bicarbonate (0.3 g/kg body weight NaHCO3) application (PR lotion; Amp Human) on blood buffering capacity and performance in recreationally active participants (study A) and moderately trained athletes (study B). Methods: In Study A, 10 participants completed 2 experimental trials: oral NaHCO3 (0.3 g/kg body weight + placebo lotion) or PR lotion (0.9036 g/kg body weight + oral placebo) applied 90 minutes prior to a cycling task to exhaustion (30-s sprints at 120% peak power output with 30-s rest). Capillary blood was collected and analyzed for pH, bicarbonate, and lactate every 10 minutes throughout the 90-minute loading period and postexercise at 5, 10, and 15 minutes. In Study B, 10 cyclists/triathletes completed 2 experimental trials, applying either PR or placebo lotion 30 minutes prior to a cycling performance task (3 × 30-s maximal sprints with 90-s recovery). Capillary blood samples were collected at baseline, preexercise, and postexercise and analyzed as per study A. Results: In Study A, pH and bicarbonate were significantly elevated from baseline after 10 minutes in the oral NaHCO3 condition and throughout recovery compared with no elevation in the PR lotion condition (P < .001). No differences in cycling time occurred between PR lotion (349 [119] s) and oral NaHCO3 (363 [80] s; P = .697). In Study B, no differences in blood parameters, mean power (P = .108), or peak power (P = .448) were observed between conditions. Conclusions: PR lotion was ineffective in altering blood buffering capacity or enhancing performance in either trained or untrained individuals.

2016 ◽  
Vol 41 (4) ◽  
pp. 354-361 ◽  
Author(s):  
Matthew F. Higgins ◽  
Susie Wilson ◽  
Cameron Hill ◽  
Mike J. Price ◽  
Mike Duncan ◽  
...  

This study evaluated the effects of ingesting sodium bicarbonate (NaHCO3) or caffeine individually or in combination on high-intensity cycling capacity. In a counterbalanced, crossover design, 13 healthy, noncycling trained males (age: 21 ± 3 years, height: 178 ± 6 cm, body mass: 76 ± 12 kg, peak power output (Wpeak): 230 ± 34 W, peak oxygen uptake: 46 ± 8 mL·kg−1·min−1) performed a graded incremental exercise test, 2 familiarisation trials, and 4 experimental trials. Trials consisted of cycling to volitional exhaustion at 100% Wpeak (TLIM) 60 min after ingesting a solution containing either (i) 0.3 g·kg−1 body mass sodium bicarbonate (BIC), (ii) 5 mg·kg−1 body mass caffeine plus 0.1 g·kg−1 body mass sodium chloride (CAF), (iii) 0.3 g·kg−1 body mass sodium bicarbonate plus 5 mg·kg−1 body mass caffeine (BIC-CAF), or (iv) 0.1 g·kg−1 body mass sodium chloride (PLA). Experimental solutions were administered double-blind. Pre-exercise, at the end of exercise, and 5-min postexercise blood pH, base excess, and bicarbonate ion concentration ([HCO3−]) were significantly elevated for BIC and BIC-CAF compared with CAF and PLA. TLIM (median; interquartile range) was significantly greater for CAF (399; 350–415 s; P = 0.039; r = 0.6) and BIC-CAF (367; 333–402 s; P = 0.028; r = 0.6) compared with BIC (313: 284–448 s) although not compared with PLA (358; 290–433 s; P = 0.249, r = 0.3 and P = 0.099 and r = 0.5, respectively). There were no differences between PLA and BIC (P = 0.196; r = 0.4) or between CAF and BIC-CAF (P = 0.753; r = 0.1). Relatively large inter- and intra-individual variation was observed when comparing treatments and therefore an individual approach to supplementation appears warranted.


2015 ◽  
Vol 25 (3) ◽  
pp. 285-292 ◽  
Author(s):  
Michael L. Newell ◽  
Angus M. Hunter ◽  
Claire Lawrence ◽  
Kevin D. Tipton ◽  
Stuart D. R. Galloway

In an investigator-blind, randomized cross-over design, male cyclists (mean± SD) age 34.0 (± 10.2) years, body mass 74.6 (±7.9) kg, stature 178.3 (±8.0) cm, peak power output (PPO) 393 (±36) W, and VO2max 62 (±9) ml·kg−1min−1 training for more than 6 hr/wk for more than 3y (n = 20) completed four experimental trials. Each trial consisted of a 2-hr constant load ride at 95% of lactate threshold (185 ± 25W) then a work-matched time trial task (~30min at 70% of PPO). Three commercially available carbohydrate (CHO) beverages, plus a control (water), were administered during the 2-hr ride providing 0, 20, 39, or 64g·hr−1 of CHO at a fluid intake rate of 1L·hr−1. Performance was assessed by time to complete the time trial task, mean power output sustained, and pacing strategy used. Mean task completion time (min:sec ± SD) for 39g·hr−1 (34:19.5 ± 03:07.1, p = .006) and 64g·hr−1 (34:11.3 ± 03:08.5 p = .004) of CHO were significantly faster than control (37:01.9 ± 05:35.0). The mean percentage improvement from control was −6.1% (95% CI: −11.3 to −1.0) and −6.5% (95% CI: −11.7 to −1.4) in the 39 and 64g·hr−1 trials respectively. The 20g·hr−1 (35:17.6 ± 04:16.3) treatment did not reach statistical significance compared with control (p = .126) despite a mean improvement of −3.7% (95% CI −8.8−1.5%). No further differences between CHO trials were reported. No interaction between CHO dose and pacing strategy occurred. 39 and 64g·hr−1 of CHO were similarly effective at improving endurance cycling performance compared with a 0g·hr−1 control in our trained cyclists.


2003 ◽  
Vol 35 (Supplement 1) ◽  
pp. S337
Author(s):  
D J. Bentley ◽  
L R. McNaughton ◽  
V E. Vleck ◽  
J Hatcher

2009 ◽  
Vol 19 (3) ◽  
pp. 275-284 ◽  
Author(s):  
Carl J. Hulston ◽  
Asker E. Jeukendrup

The purpose of this study was to investigate the possibility of a placebo effect from carbohydrate (CHO) intake during prolonged exercise. Ten endurance-trained male cyclists performed 3 experimental trials consisting of 120 min of steady-state cycling at 61% VO2max followed by a time trial (TT) lasting approximately 60 min. During exercise participants ingested either plain water (WAT), artificially colored and flavored water (PLA), or a 6% carbohydrate-electrolyte solution (CES). PLA and CES were produced with identical color and taste. To investigate the possibility of a placebo effect from CHO intake, participants were told that both flavored solutions contained CHO and that the purpose of the study was to compare CHO drinks with water. Mean power output during TT was 218 ± 22 W in WAT, 219 ± 17 W in PLA, and 242 ± 27 W in CES. Performance times were 66.35 ± 6.15, 65.94 ± 5.56, and 59.69 ± 2.87 min for WAT, PLA, and CES, respectively. Therefore, CES ingestion enhanced TT performance by 11.3% compared with WAT (p < .05) and 10.6% compared with PLA (p < .05), with no difference between PLA and WAT. In conclusion, during a prolonged test of cycling performance, in which participants were not fully informed of the test conditions, there was no placebo effect when participants believed they had ingested CHO. In contrast, the real effect of CHO intake was a 10.6% improvement in TT cycling performance.


2007 ◽  
Vol 17 (2) ◽  
pp. 206-217 ◽  
Author(s):  
Guilherme Giannini Artioli ◽  
Bruno Gualano ◽  
Desiré Ferreira Coelho ◽  
Fabiana Braga Benatti ◽  
Alessandra Whyte Gailey ◽  
...  

The aim of the present study was to investigate whether pre exercise sodium-bicarbonate ingestion improves judo-related performance. The study used 2 different protocols to evaluate performance: 3 bouts of a specific judo test (n = 9) and 4 bouts of the Wingate test for upper limbs (n = 14). In both protocols athletes ingested 0.3 g/kg of sodium bicarbonate or placebo 2 h before the tests. Blood samples were collected to determine lactate level, and levels of perceived exertion were measured throughout the trials. The study used a double-blind, counterbalanced, crossover design. Ingestion of sodium bicarbonate improved performance in Bouts 2 and 3 of Protocol 1 (P < 0.05), mean power in Bouts 3 and 4 of Protocol 2 (P < 0.05), and peak power in Bout 4 of Protocol 2 (P < 0.05). Ingestion of bicarbonate increased lactate concentration in Protocol 1 (P < 0.05) but not in Protocol 2. Ratings of perceived exertion did not differ between treatments. In conclusion, sodium bicarbonate improves judo-related performance and increases blood lactate concentration but has no effect on perceived exertion.


2014 ◽  
Vol 24 (6) ◽  
pp. 605-612 ◽  
Author(s):  
Edwin Chong ◽  
Kym J. Guelfi ◽  
Paul A. Fournier

This study investigated whether combined ingestion and mouth rinsing with a carbohydrate solution could improve maximal sprint cycling performance. Twelve competitive male cyclists ingested 100 ml of one of the following solutions 20 min before exercise in a randomized double-blinded counterbalanced order (a) 10% glucose solution, (b) 0.05% aspartame solution, (c) 9.0% maltodextrin solution, or (d) water as a control. Fifteen min after ingestion, repeated mouth rinsing was carried out with 11 × 15 ml bolus doses of the same solution at 30-s intervals. Each participant then performed a 45-s maximal sprint effort on a cycle ergometer. Peak power output was significantly higher in response to the glucose trial (1188 ± 166 W) compared with the water (1036 ± 177 W), aspartame (1088 ± 128 W) and maltodextrin (1024 ± 202W) trials by 14.7 ± 10.6, 9.2 ± 4.6 and 16.0 ± 6.0% respectively (p < .05). Mean power output during the sprint was significantly higher in the glucose trial compared with maltodextrin (p < .05) and also tended to be higher than the water trial (p = .075). Glucose and maltodextrin resulted in a similar increase in blood glucose, and the responses of blood lactate and pH to sprinting did not differ significantly between treatments (p > .05). These findings suggest that combining the ingestion of glucose with glucose mouth rinsing improves maximal sprint performance. This ergogenic effect is unlikely to be related to changes in blood glucose, sweetness, or energy sensing mechanisms in the gastrointestinal tract.


Author(s):  
Manuel V Garnacho-Castaño ◽  
Arturo Muñoz-González ◽  
María A Garnacho-Castaño ◽  
José L Maté-Muñoz

Knowledge of the power– and velocity–load relationships is a key factor to guide loads during resistance training and optimize sports performance. This study compares mean velocity–, peak velocity– and power–load relationships, and determines the load which elicits maximal power output in the military press and bench press. Fifty-seven healthy, active men were randomly assigned to a bench press (n = 28) or military press (n = 29) group. In separate test sessions, concentric-only or eccentric-concentric sequences of each exercise were performed in random order as incremental isoinertial load tests. Both mean velocity and peak velocity were highly related with the load lifted (% 1RM) in both bench press and military press (mean velocity: R2 = 0.94 and 0.95; peak velocity: R2 = 0.93 and 0.93, respectively). The loads maximizing mean power and peak power output were similar for the eccentric-concentric versus concentric sequences in bench press and military press. The loads maximizing mean power and peak power were between 54% and 57.5% 1RM for the bench press and 59.8%–63.1% 1RM for the military press. For the bench press, no significant differences were observed in mean power from 30% to 80% 1RM and peak power from 30% to 95% 1RM. For the military press, no significant differences were observed in mean power from 40% to 80% 1RM and peak power from 30% to 90%/95% 1RM. The close relationship detected between mean velocity or peak velocity and load means that the % 1RM can be estimated according to mean velocity and peak velocity. In both exercises, a broad range of relative intensities could be used at which power output is not significantly different than that at maximized power output (mean = 30%/40%–80% 1RM; peak = 30%–90%/95%). Mean velocity lower than approximately 0.33 m s−1 for bench press and 0.4 m s−1 for military press, as well as peak velocity lower than approximately 0.4 m s−1 for bench press and 0.5 m s−1 for military press do not optimize power output responses. The eccentric action was a determining factor for increasing power output only in bench press.


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