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Christopher M. Carr

This paper describes one psychologist’s professional journey providing clinical sport psychological services to student athletes, from training to first position, and on to current roles and responsibilities. Obstacles in providing psychological care to student-athletes in the intercollegiate setting are highlighted and an approach to overcoming these obstacles is articulated. Most importantly, this paper highlights the consequences of both interdisciplinary conflict within sport psychology and poorly trained professionals. The importance of ongoing professional development for both the individual practitioner and the field of sport psychology as a whole is thoroughly presented and discussed.

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Amelia J. Carr, Gary J. Slater, Christopher J. Gore, Brian Dawson and Louise M. Burke

Purpose:

The aim of this study was to determine the effect and reliability of acute and chronic sodium bicarbonate ingestion for 2000-m rowing ergometer performance (watts) and blood bicarbonate concentration [HCO3 ].

Methods:

In a crossover study, 7 well-trained rowers performed paired 2000-m rowing ergometer trials under 3 double-blinded conditions: (1) 0.3 grams per kilogram of body mass (g/kg BM) acute bicarbonate; (2) 0.5 g/kg BM daily chronic bicarbonate for 3 d; and (3) calcium carbonate placebo, in semi-counterbalanced order. For 2000-m performance and [HCO3 ], we examined differences in effects between conditions via pairwise comparisons, with differences interpreted in relation to the likelihood of exceeding smallest worthwhile change thresholds for each variable. We also calculated the within-subject variation (percent typical error).

Results:

There were only trivial differences in 2000-m performance between placebo (277 ± 60 W), acute bicarbonate (280 ± 65 W) and chronic bicarbonate (282 ± 65 W); however, [HCO3 ] was substantially greater after acute bicarbonate, than with chronic loading and placebo. Typical error for 2000-m mean power was 2.1% (90% confidence interval 1.4 to 4.0%) for acute bicarbonate, 3.6% (2.5 to 7.0%) for chronic bicarbonate, and 1.6% (1.1 to 3.0%) for placebo. Postsupplementation [HCO3 ] typical error was 7.3% (5.0 to 14.5%) for acute bicarbonate, 2.9% (2.0 to 5.7%) for chronic bicarbonate and 6.0% (1.4 to 11.9%) for placebo.

Conclusion:

Performance in 2000-m rowing ergometer trials may not substantially improve after acute or chronic bicarbonate loading. However, performances will be reliable with both acute and chronic bicarbonate loading protocols.

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Amelia J. Carr, Gary J. Slater, Christopher J. Gore, Brian Dawson and Louise M. Burke

Context:

Sodium bicarbonate (NaHCO3) is often ingested at a dose of 0.3 g/kg body mass (BM), but ingestion protocols are inconsistent in terms of using solution or capsules, ingestion period, combining NaHCO3 with sodium citrate (Na3C6H5O7), and coingested food and fluid.

Purpose:

To quantify the effect of ingesting 0.3 g/kg NaHCO3 on blood pH, [HCO3−], and gastrointestinal (GI) symptoms over the subsequent 3 hr using a range of ingestion protocols and, thus, to determine an optimal protocol.

Methods:

In a crossover design, 13 physically active subjects undertook 8 NaHCO3 experimental ingestion protocols and 1 placebo protocol. Capillary blood was taken every 30 min and analyzed for pH and [HCO3−]. GI symptoms were quantified every 30 min via questionnaire. Statistics used were pairwise comparisons between protocols; differences were interpreted in relation to smallest worthwhile changes for each variable. A likelihood of >75% was a substantial change.

Results:

[HCO3−] and pH were substantially greater than in placebo for all other ingestion protocols at almost all time points. When NaHCO3 was coingested with food, the greatest [HCO3−] (30.9 mmol/kg) and pH (7.49) and lowest incidence of GI symptoms were observed. The greatest incidence of GI side effects was observed 90 min after ingestion of 0.3 g/kg NaHCO3 solution.

Conclusions:

The changes in pH and [HCO3−] for the 8 NaHCO3-ingestion protocols were similar, so an optimal protocol cannot be recommended. However, the results suggest that NaHCO3 coingested with a high-carbohydrate meal should be taken 120–150 min before exercise to induce substantial blood alkalosis and reduce GI symptoms.