People feel like they’re working much harder during a 30-minute hydraulic machine HIIT workout than during weightlifting, running, or biking, even though they’re resting part of the time.
Scientific Claim
The rating of perceived exertion (RPE) during a 30-minute hydraulic resistance system (HRS) high-intensity interval training session in healthy men averages 16 ± 2 on the Borg 6–20 scale, which is significantly higher than during resistance training (13 ± 2), treadmill endurance (10 ± 2), or cycling endurance (11 ± 1).
Original Statement
“Similarly, the average RPE was significantly (p ≤ 0.05) higher with the HRS (16 ± 2), compared with that using weights (13 ± 2), treadmill (10 ± 2), and cycle (11 ± 1).”
Evidence Quality Assessment
Claim Status
appropriately stated
Study Design Support
Design supports claim
Appropriate Language Strength
definitive
Can make definitive causal claims
Assessment Explanation
RPE is a direct self-reported measure collected under standardized conditions. The claim reports observed values and statistical differences without implying causation or generalizability, making definitive language appropriate.
Gold Standard Evidence Needed
According to GRADE and EBM methodology, here is what ideal scientific evidence would look like to definitively prove or disprove this specific claim, ordered from strongest to weakest evidence.
Systematic Review & Meta-AnalysisLevel 1aWhether HRS-HIIT consistently elicits higher RPE than other modalities across populations and protocols.
Whether HRS-HIIT consistently elicits higher RPE than other modalities across populations and protocols.
What This Would Prove
Whether HRS-HIIT consistently elicits higher RPE than other modalities across populations and protocols.
Ideal Study Design
A meta-analysis of crossover studies comparing RPE during 30-minute HRS-HIIT, resistance, treadmill, and cycling sessions in healthy adults, using the Borg 6–20 scale at standardized time points, with controlled intensity and environmental conditions.
Limitation: RPE is subjective and influenced by individual motivation and expectations.
Randomized Controlled TrialLevel 1bWhether HRS-HIIT causes higher perceived exertion than other modalities in a controlled setting.
Whether HRS-HIIT causes higher perceived exertion than other modalities in a controlled setting.
What This Would Prove
Whether HRS-HIIT causes higher perceived exertion than other modalities in a controlled setting.
Ideal Study Design
A randomized crossover RCT with 50+ healthy adults performing all four 30-minute exercise conditions in random order, with RPE recorded every 5 minutes using the Borg scale, under blinded conditions for data collection.
Limitation: Does not account for long-term adaptation or changes in perceived effort with training experience.
Cross-Sectional SurveyLevel 3Whether individuals who regularly use HRS report higher perceived exertion during workouts than users of other modalities.
Whether individuals who regularly use HRS report higher perceived exertion during workouts than users of other modalities.
What This Would Prove
Whether individuals who regularly use HRS report higher perceived exertion during workouts than users of other modalities.
Ideal Study Design
A cross-sectional survey of 500+ regular exercisers who use HRS, resistance, treadmill, or cycling as their primary modality, asking them to rate RPE during their typical 30-minute session using the Borg scale, controlling for fitness level and training frequency.
Limitation: Retrospective recall bias and lack of experimental control.
Evidence from Studies
Supporting (1)
The study had men do a 30-minute intense workout using a hydraulic machine and found they felt it was much harder (RPE of 16) than lifting weights, running on a treadmill, or cycling — exactly what the claim says.