The Acute Effects of Liquid IV's Pre-Workout Supplement on Muscle Endurance & Strength, Energy, and Cognition

Participants will complete a graded cycling test on a calibrated cycle ergometer to assess aerobic performance. Maximal oxygen consumption (VO₂max) will be noted if a plateau is observed. using a metabolic cart to determine VO₂max.VO₂max represents the highest rate of oxygen consumption achieved during the test. Proper cycle ergometer setup, including seat height and handlebar position, will be standardized for all participants. Testing will be conducted by trained technicians for consistency.

Participants will complete bench press assessments to evaluate muscular strength and endurance. A 5-repetition maximum (5RM) protocol will be used to determine maximal bench press strength. For muscular endurance, participants will complete two sets of bench press at 60% of their 1RM, performing repetitions to fatigue with 2 minutes of rest between sets. Total work volume will be calculated as the product of sets × repetitions. Proper spotting and form supervision will be ensured throughout.

Participants will complete a graded cycling test on a calibrated cycle ergometer to assess aerobic performance. Oxygen consumption (VO₂) will be continuously monitored every 15 seconds using a metabolic cart to determine VO₂peak. Peak oxygen consumption will be recorded as the highest oxygen uptake value observed during the incremental test. Proper cycle ergometer setup, including seat height and handlebar position, will be standardized for all participants. Testing will be conducted by trained technicians for consistency.

Participants will complete a graded cycling test on a calibrated cycle ergometer to assess aerobic performance. The total duration in minutes participants are able to sustain the incremental cycling workload until volitional fatigue is recorded. This measures endurance capacity during the graded test. Proper cycle ergometer setup, including seat height and handlebar position, will be standardized for all participants. Testing will be conducted by trained technicians for consistency.

Participants will complete a graded cycling test on a calibrated cycle ergometer to assess aerobic performance. Total work (kJ) will be calculated as Σ(power × time)/1000, where power = kp × 50 RPM × 6.118.. This reflects overall exercise performance. Proper cycle ergometer setup, including seat height and handlebar position, will be standardized for all participants. Testing will be conducted by trained technicians for consistency.

The Thayer ADACL is a 20-item self-report scale used to assess participants' current mood states across four subscales: Energetic Arousal, Tense Arousal, Calmness, and Fatigue. Participants indicate the extent to which each adjective describes their current state on a 4-point scale ranging from 1 ("definitely feel") to 4 ("definitely do not feel"). Higher scores on Energetic Arousal and Calmness indicate greater energy and calmness, while higher scores on Tense Arousal and Fatigue indicate greater tension and fatigue. Two items, "wide-awake" and "wakeful," are reverse-scored as part of the Fatigue subscale to ensure that higher subscale scores consistently reflect greater fatigue. Subscale scores are analyzed individually to evaluate changes in mood and energy/fatigue responses to supplementation.

The Samn-Perelli VAS is a single-item scale used to assess participants' subjective levels of alertness and fatigue. Participants mark a point along a 7-point scale, where 1 indicates "fully alert" and 7 indicates "completely exhausted." Higher scores reflect greater fatigue or lower alertness. This measure allows quantification of perceived fatigue before and after supplementation, and changes from baseline are used to evaluate the intervention's effects.

The Caffeine VAS is a multi-item visual analog scale used to assess participants' perceived alertness, fatigue, and potential side effects related to caffeine intake. Participants indicate their current state by marking a point along a 100-mm horizontal line, where 0 represents "not at all" and 100 represents "extremely." Scores are recorded in millimeters from the left anchor, with higher values indicating greater intensity of the measured state. Each item is scored separately, and changes from baseline are used to evaluate the effects of supplementation.

Maximal lower-body strength will be assessed using a calibrated isometric mid-thigh pull device. Participants will perform a single maximal effort pull while maintaining standardized body posture and hand placement on the bar. Peak force output, measured in Newtons, will be recorded as the primary indicator of lower-body strength. All tests will be administered by the same technician to ensure procedural consistency.

The force plate platform consists of two force plates (left & right) containing four force sensors which measure ground reaction force. The sensors are connected to a laptop and analyzed using Mechanography GRFP Research Edition® software (version 4.2-b05.53-RES). Subjects will perform three maximal vertical CMJs on a calibrated force plate. Subjects will be instructed to stand upright on the center of the force plate with feet shoulder-width apart and hands placed on the hips. Subjects will perform a maximal effort vertical jump with proper form and instructed to land with soft knees and remain still after each jump for data capture. A 30sec rest period will be provided between each trial. Data will be used to assess maximum force output (Fmax), rate of force development (RFD), jump height (inches), and maximum power (Pmax). Force curves will be reviewed for each trial, and results averaged. This will quantify full-body mechanical power under standardized, reproducible conditions.

Hydration and body water distribution will be assessed using bioelectrical impedance analysis. Parameters include total body water (TBW), extracellular water (ECW), and intracellular water (ICW). Participants will be instructed to arrive in a fasted state, and measurements will be taken under standardized conditions to determine body hydration levels. These values provide insight into overall hydration and fluid compartment balance.

Handgrip strength will be evaluated using a calibrated hand grip dynamometer. Participants will perform three maximal isometric contractions with their dominant hand, with 30 seconds of rest between attempts. The highest recorded value (in kilograms of force) will be used for analysis. This assessment provides an index of upper-body muscular strength.

Urine specific gravity will be measured using a handheld refractometer to assess acute hydration status. Participants will provide a midstream urine sample, and the specific gravity value will be recorded to the nearest 0.001. Lower values indicate greater hydration, while higher values suggest increased concentration or dehydration.

Time Frame: Assessed at baseline and post-supplementation testing.