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| Name | Class |
|---|---|
| University of Stellenbosch | OTHER |
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The study aims to investigate the effects of post-exercise and pre-sleep ketosis via oral ketone ester supplementation on physical and mental recovery during a multi-day cycling stage race.
Ultra-endurance events are becoming increasing popular. Participation in the multi-day events adds a lot of physical and mental strain on the body, while the athletes are still required to perform. Without appropriate recovery the athletes are at increased risk of overreaching, injury, or illness.
Therefore, the purpose of the study is to create a better understanding of the exercise fatigue experienced during ultra-endurance performance and the role intermittent exogenous ketosis (IEK) plays in reducing the amount of fatigue to maintain performance during multi-day racing and lower the risk of injury and illness.
Participants will first compete in a 8-day simulated stage race performed on taxc trainers and then we will conduct a field study during the Absa Cape Epic a 8-day mountain bike stage race. Immediately following each stage and 30-mins before bed the participants will consume either a ketone ester and taste-match placebo drink. During the race the following variables will be measured; hydration status, weight change, activity readiness, and nutrition intake. Cognitive function will be assessed on day 2, 4 and 8 of racing. One day before and one day after the race the participants will report to the lab to assess basal metabolic rate, stress via questionnaires, appetite, cognitive function, muscle biopsies, venous blood samples, mechanical efficiency and 30-min Time Trial.
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| Label | Type | Description | Intervention Names |
|---|---|---|---|
| Control group | Placebo Comparator | Intervention: 8-day multistage mountain bike race/simulation Dietary intervention: placebo supplement (oral supplement containing: 16.4 grams of medium chained triglycerides, 1mM of sucrose octaacetate and water) |
|
| Experimental group | Experimental | Intervention: 8-day multistage mountain bike race/simulation Dietary intervention: ketone ester supplement (25 grams of pure R-(3)-hydroxybutyl-(R)-3-hydroxybutyrate ketone monoester drink) |
|
| Name | Type | Description | Arm Group Labels | Other Names |
|---|---|---|---|---|
| Placebo Supplement | Dietary Supplement | Placebo supplement: Oral supplement containing: 16.4 grams of medium chained triglycerides, 1mM or sucrose octaacetate and water |
|
| Measure | Description | Time Frame |
|---|---|---|
| Muscle soreness | Visual analog scale (0-10) How sore does you leg muscles feel? The VAS was used as a subjective measure of muscle soreness | During the intervention |
| Physical stress | RESTQ-76 sport questionnaire was used to assess the stress-recovery balance | pre-intervention and 1 day after the intervention |
| Hydration status | Before every stage, the participants provided a urine sample in a cup. A urine-specific refractometer (Atago) was used to determine their hydration status | Baseline, During the intervention and 1 day after the intervention |
| Cognitive function: reaction time | CANTAB test battery reaction time test was used to determine reaction time in milliseconds. | Pre-intervention, day 2, 4 and 8 of the intervention |
| Cognitive function: rapid visual processing | CANTAB test battery rapid visual processing test was used to assess their susceptibility to false alarms | Pre-intervention, day 2, 4 and 8 of the intervention |
| Cognitive function: swm | CANTAB spatial working memory test was used to access executive function; the main outcome measure used was the number of errors | Pre-intervention, day 2, 4 and 8 of the intervention |
| Sleep Duration | Fitbit inspire 3 was used to measure sleep duration (hours:minutes:seconds) |
| Measure | Description | Time Frame |
|---|---|---|
| Mechanical efficiency | Mechanical efficiency will be determined during three constant load (100 watts, 150 watts, and 200 watts) cycling bouts of 5 minutes on a calibrated ergometer (Avantronic Cyclus II). Throughout the test, gas exchange will continuously be measured using calibrated metabolic analyzer with a face mask (Cortex, Metalyzer IIIb). VO2 and VCO2 data of the final minute of each workload will be used to calculate gross efficiency (%). |
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Inclusion Criteria:
Exclusion Criteria:
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| Name | Affiliation | Role |
|---|---|---|
| Chiel Poffé | KU Leuven | Principal Investigator |
| Facility | Status | City | State | ZIP | Country | Contacts |
|---|---|---|---|---|---|---|
| KU Leuven | Leuven | Vlaams-Brabant | 3000 | Belgium |
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| ID | Term |
|---|---|
| D005221 | Fatigue |
| D005222 | Mental Fatigue |
| ID | Term |
|---|---|
| D012816 | Signs and Symptoms |
| D013568 | Pathological Conditions, Signs and Symptoms |
| D001526 | Behavioral Symptoms |
| D001519 | Behavior |
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Riders will be paired matched and randomly assigned to either the ketone ester supplementation (KE) group or the control group (CON) which will receive an isocaloric taste-matched placebo
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Participants and investigators are blinded from the experimental condition (KE or CON). Supplements are provided in non transparent tubes and the control supplement is identical in taste and viscosity to the ketone supplement.
| Ketone ester supplement | Dietary Supplement | Ketone ester supplement Oral supplement containing: 25 grams of pure (R)-3-hydroxybutyl-(R)-3-hydroxybutyrate ketone monoester drink |
|
| 1 week prior to racing and during the race |
| Sleep: REM | The Fitbit Inspire 3 was used to measure the total duration of rapid eye motion (REM)sleep during each night for the duration of the study. The REM sleep phase will be analysed in minutes | 1 week prior to racing and during the race |
| Sleep: Non-REM | The Fitbit Inspire 3 will be used to determine the NON-REM sleep phase for each night in minutes | 1 week prior to racing and during the race |
| Sleep: WASO | The FITBIT inspire 3 will be used to measure wake after sleep onset in minutes for each night | 1 week prior to racing and during the race |
| pre-intervention and 1 day after the intervention |
| Time trial performance | The participants will perform a 30-minute time trial. The average power output (watts) achieved will be used as the outcome measure. | pre-intervention and 1 day after the intervention |
| Appetite | Appetite will be assessed with a Likert visual analog scale (0-10) using the following four questions: "How hungry do you feel?" "How full do you feel?" "How satisfied do you feel?" "How much do you think you could eat now?" | pre-intervention, during the intervention, 1 day after the intervention |
| Macronutrient intake | Participants will complete a food diary using the Mijnetemeter application on their phone. Total fat, protein and carbohydrate intake will be determined in grams for each day. | baseline, during the intervention |
| Total energy intake | Participants will complete a food diary, using the Mijnetemeter application on their phones. total energy intake (kilojoules) will be calculated for each day. | baseline, during the intervention |
| Racing intensity | hear rate zones during racing | during each stage |
| Body weight change | Body mass was measured using a SECA, model 813 electrical scale, before and after each stage as a secondary method to assess hydration status. Body mass was measured to the nearest 0.1 kilogram | During the intervention |