The effectiveness of pre-exercise caffeine in maximizing hypertrophy and strength gains from morning resistance training in older adults

To investigate whether acute pre-exercise morning caffeine ingestion, combined with daily multi-ingredient nutritional supplementation (whey protein, creatine monohydrate, and omega-3 PUFAs), enhances hypertrophic and strength adaptations after a 12-week resistance training program in older adults, compared with morning or afternoon training with nutritional supplementation alone (no caffeine).

A randomized, double-blind, placebo-controlled, parallel-group phase 3 study in 60 elderly men. The RAND function in Excel will be used for randomization.

Participants will be randomly allocated (1:1:1 stratified by sex and baseline strength) into one of three parallel groups: MOR-CAF, MOR-PLA, or AFT-PLA. They will complete 12 weeks of supervised resistance training (3 sessions/week; ~65–80% 1RM). The study will be conducted in Ankara, Turkey.

Inclusion criteria: Low habitual caffeine intake (<100 mg/day); recreationally active but not accustomed to structured resistance training over the preceding 6 months. Exclusion criteria: uncontrolled cardiovascular, metabolic, or respiratory disease; having sleep disorders; use of medications known to alter neuromuscular function or sleep architecture.

MOR-CAF group, morning training (8:00) + pre-training caffeine (4 mg/kg) + daily multi-ingredient supplementation; MOR-PLA group, morning training (8:00) + pre-training placebo + daily multi-ingredient supplementation; AFT-PLA group, afternoon training (17:00) + pre-training placebo + daily multi-ingredient supplementation.

Maximal strength, muscular endurance, muscle thickness, and body composition will be assessed before and after the intervention.

To minimize potential differences between groups, participants will first be grouped based on their average 1-repetition maximum strength in the squat and bench press. The names of the subjects in each group will be entered into an Excel column; each subject will be randomly assigned a number using the RAND function (=RAND()); then, the numbers will be sorted from smallest to largest. Subjects in each group will then be randomly assigned to one of three groups in a 1:1:1 fashion: caffeine and exercise in the morning, placebo and exercise in the morning, or placebo and exercise in the afternoon.

Someone outside the study will prepare the supplement and placebo and will not be known to the participants or researchers until after the data analysis. Also, subjects will receive the supplement and placebo in an opaque capsule with a completely similar appearance and weight, and at the same time of day.

All data collected during the study will be shareable after de-identifying the subjects.

The data will be published after the extracted articles are accepted.

All people

All data collected during the study will be shareable after de-identifying the subjects. The requester will only be permitted to use the data for meta-analysis reviews.

Corresponding author: Davar Khodadadi, Faculty of Physical Education and Sports Sciences, Islamic Azad University Central Tehran Branch, Tehran, Iran. Email: davar.khodadadi@yahoo.com

Sending an email request to the corresponding author: Davar Khodadadi, Email: davar.khodadadi@yahoo.com