NO EFFECT OF KETOSIS AND DEHYDRATION ON BORG RATING OF PERCEIVED EXERTION DURING A 50 KM MOUNTAIN ULTRA-MARATHON
Bibliographic record
Abstract
PURPOSE: The purpose of this study was to assess if runners who produced ketones and were dehydrated gave greater Borg Ratings of Perceived Exertion (BRPE) during a 50 km mountain ultra-marathon. HYPOTHESIS: It was hypothesized that the increase of BPRE would be greater in the ketone production group as compared to non-ketone producing group. METHODS: Sixteen healthy adults volunteered for this study. Their average age was 44.1+9.4 y (mean±SD), height 1.8+0.1 m, body mass 72.5+9.2 kg, BMI 23.0+2.6 kg•m-2. The office of research ethics at SFU approved the study and each volunteer gave a signed consent prior to participation. Each volunteer provided a pre-race urine sample and BRPE (unit less), then completed a 50 km mountain ultra-marathon, with 3 additional BRPE assessments during the race, and then gave a post-race urine sample and a final BRPE. Qualitative and semi-qualitative urine stripes were used to determine ketone presence in urine samples and urine specific gravity was measured with urinometer. A mixed model ANOVA was employed with the main effects of Distance (0%, 25%, 50%, 75% and 100% of 50 km) and Ketosis State (Ketone Producing and Non-Ketone Producing). The P-value was set at 0.05. RESULTS: Six participants were found to produce ketones in post-race urine samples and were dehydrated with a post-race urine specific gravity of 1.031. Ten participants were found to not produce ketones with a post-race urine specific gravity of 1.019. There was a significant difference in urine specific gravity between the ketone and non-ketone producing group (p<0.05). There was a significant main effect of Distance (F=6.2, p<0.01) on BRPE but no main effect of Ketosis State nor an interaction (F=1.8, p=0.20) between Distance and Ketosis State. The mean BRPE across groups (n=16) ranged from 7.0±1.2 at the start to 15.1±4.4 at the end of the race. CONCLUSION: These preliminary results suggest factors other than ketone production and the associated dehydration cause a rise in BPRE during the course of a mountain ultra-marathon. Supported by the Natural Sciences and Engineering Research Council of Canada and The Canadian Foundation for Innovation
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".