Beta-alanine Supplementation and Its Effects on Performance, Muscle Carnosine Content and Safety in Athletes With Spinal-cord Injury

Study Overview
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Brief Summary
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Paralympians competing in wheelchair sports may experience a very high glycolytic demand (and therefore acidotic environment) in their upper-body muscles, particularly in high-intensity disciplines. Previous studies from our group have shown that upper-body exercise is very sensitive to the ergogenic effects of β-alanine supplementation and to other nutritional supplements capable of increasing buffering capacity. In line with this, have shown that upper-body muscle groups benefit more from artificially induced alkalosis than lower-body muscle groups. Although β-alanine appears to be an interesting and potential ergogenic supplement for paralympians, no study to date has assessed its potential in wheelchair athletes.In this study, we will evaluate the effects of β-alanine supplementation on upper-body performance in wheelchair athletes.

Conditions
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Spinal Cord Injuries

Intervention / Treatment
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* Dietary Supplement: Beta-alanine
* Dietary Supplement: Dextrose


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Paralympian training for any exercise modality for at least one year; A weekly training volume of 6 hours or more; Have a spinal cord injury accompanied by loss of motor function in the lower limbs for at least one year; Available for carrying out the experimental procedures. Exclusion Criteria: Use of creatine or beta-alanine for at least 3 and 6 months before the trial; Cardiovascular or respiratory disease; Clinical condition that result in malabsorption of nutrients; Any other medical condition that prevents the realization of experimental procedures.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 40 Years

Sexes Eligible for Study
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Male

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Placebo Comparator: Placebo<br>800 mg of dextrose, four times per day, during 28 days. | Dietary Supplement: Dextrose<br> <br> |
| Experimental: Beta-alanine<br>800 mg of beta-alanine, four times per day, during 28 days. | Dietary Supplement: Beta-alanine<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Exercise performance (Time to exhaustion test) | Time to exhaustion test performed on arm crank ergometer | 28 days | 
| Muscle carnosine content before and after supplementation | Assessed by muscle biopsy samples before performance tests | 28 days | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Muscle carnosine content in trained (deltoid) vs. untrained (vastus lateralis) muscles | Deltoids microbiopsy and vastus lateralis biopsy | 28 days | 
| Blood pH. | 1 mL venous blood sample | 5 minutes after performance tests | 
| Safety of beta-alanine supplementation measured by complete hemogram analysis |  | 28 days |