Caffeine and Resistance Training
Conditions
Brief summary
Introduction: Several studies have evaluated and confirmed the ergogenic effect of acute caffeine intake on sports performance, specifically on strength and power performance. However, little is known about the prolonged effect of this supplement on neuromuscular adaptations to strength training. Introduction: Several studies have evaluated and confirmed the ergogenic effect of acute caffeine intake on sports performance, specifically on strength and power performance. However, little is known about the prolonged effects of this supplement on neuromuscular adaptations to strength training. Objectives: The present study aims to analyze the effects of acute and chronic caffeine intake on neuromuscular adaptations to strength training, according to sex (men vs. women) and type of exercise (bench press vs. squat), as well as on fatigue resistance during repeated sprints, fatigue perception, mood state, reaction time, diet, and potential side effects.
Interventions
Acute caffeine intake (3 mg/kg) prior each resistance training session of a 8 weeks training program.
Acute placebo intake (3 mg/kg of maltodextrin) prior each resistance training session of a 8 weeks training program.
Sponsors
Study design
Masking description
Statistician
Intervention model description
Randomized controlled trial
Eligibility
Inclusion criteria
* Age between ≥ 18 and ≤ 35 years. * Body mass index (BMI) < 25 kg/m². * Physically active subjects (>150 min/week of moderate exercise). * Healthy men and women without neurological, cardiometabolic, immunological, or physical conditions that prevent them from performing physical exercise. * Participants capable of performing the tests.
Exclusion criteria
* History of neuromuscular, cardiac, or diseases that could affect liver or muscle metabolism. * Use of drugs or other stimulants that interfere with caffeine intake and intestinal absorption during the tests and study. * Body mass index (BMI) > 25 kg/m². * Having undergone prolonged periods of forced physical inactivity during the 6 months prior to the study. * Performing strenuous exercise within 48 hours prior to the tests. * Failing to replicate the same food intake on the two experimental days. * Consuming caffeine after 6 PM on the day prior to training or testing.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Mean velocity at different %1RM | Through study completion, an average of 12 weeks | Measuring bar mean velocity desplacement during bench press and back squat exercises. |
| Peak velocity at different %1RM | Through study completion, an average of 12 weeks | Measuring bar peak velocity and time to reach peak velocity of bar desplacement during bench press and back squat exercises. |
| Mean power output at different %1RM | Through study completion, an average of 12 weeks | Measuring during bench press and back squat exercises. |
| Peak power output and time to reach peak power output at different %1RM | Through study completion, an average of 12 weeks | Measuring during bench press and back squat exercises. |
| Number of repetitions performed at 65%1RM until task failure | Through study completion, an average of 12 weeks | In bench press and back squat exercises |
| Bar velocity deplacement performed in 1 set at 65%1RM until task failure | Through study completion, an average of 12 weeks | In bench press and back squat exercises |
| Power output generated in 1 set at 65%1RM until task failure | Through study completion, an average of 12 weeks | In bench press and back squat exercise |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Resting Metabolic Rate (RMR) | Through study completion, an average of 12 weeks | Kcal at rest using a metabolic chart. |
| Adverse effects | Through study completion, an average of 12 weeks | Adverse effects. perception of power, endurance, energy and exertion, as well as heart, muscular and gastrointestinal discomfort. |
| Maximal Fat Oxidation Rate (MFO) | Through study completion, an average of 12 weeks | g/min using a metabolic chart. |
| Fat mass | Through study completion, an average of 12 weeks | Using electrical bioimpedance (kg and % of body mass) |
| Fat-free mass | Through study completion, an average of 12 weeks | Using electrical bioimpedance (kg and % of body mass) |
| Physical activity (METs-min/wk) | Through study completion, an average of 12 weeks | Using IPAQ |
| Dietary (g/kg of macronutrients) | Through study completion, an average of 12 weeks | Using a 24-total recall |
| Mood state | Through study completion, an average of 12 weeks | Mood. Participants graded a set of 29 items related to the mood on a Likert scale from 0 (not at all) to 4 (extremely) in reply to the question;How do you feel at this moment?; to assess six scales: tension, depression, anger, vigor, fatigue and confusion. |
Countries
Spain