High-Intensity Training backed by 40+ years of research. 15-20 minute workouts, 2-3x per week. Maximum results, minimum time.
HIT is a strength training methodology that emphasizes brief, intense workouts focusing on slow, controlled movements to complete muscle fatigue. One set per exercise is all you need.
Complete workouts in 15-20 minutes. Research shows single sets to failure produce 90-95% of the gains from multiple-set programs.
Decades of peer-reviewed research demonstrate HIT produces equal or superior results compared to traditional high-volume training.
Slow, controlled movements minimize joint stress while maximizing muscle tension. No ballistic movements or heavy impact.
The secret to HIT's effectiveness lies in extended time under tension and the elimination of momentum.
Each exercise lasts 90+ seconds of continuous muscle engagement. Traditional lifting with momentum only provides 10-20 seconds of actual tension per set.
By removing momentum and maintaining constant tension, you reach genuine muscular failure - the primary trigger for muscle growth and strength adaptation.
Fast lifting uses momentum to move weight. Slow lifting forces your muscles to do 100% of the work. This is why slower is actually harder - and more effective.
Explosive movements create peak forces 3-5x the actual weight. Slow, controlled movements keep force consistent and manageable, protecting joints and connective tissue.
Brief, intense workouts require less recovery than high-volume programs. Train 2-3x per week with full recovery between sessions for continuous progress.
High-Intensity Training isn't a fad - it's backed by over four decades of scientific research and real-world results.
A 2017 meta-analysis of 14 studies found no significant difference in strength gains between single-set and multiple-set training when sets are taken to failure. Single sets are equally effective while requiring 1/3 the time.
Journal of Sports Medicine, 2017Studies with adults over 50 show HIT protocols produce significant muscle gains (8-12 lbs of lean mass in 10-12 weeks) while simultaneously reducing body fat.
Dr. Ellington Darden Research, 2012-2018A University of Florida study found that one set of 8-12 exercises performed twice weekly produced the same strength gains as three sets performed three times weekly.
University of Florida, 1998High-intensity resistance training stimulates bone formation and increases bone mineral density, crucial for preventing osteoporosis. Slow, controlled movements are particularly effective.
Journal of Bone and Mineral ResearchResearch shows brief, intense resistance training provides cardiovascular benefits comparable to traditional aerobic exercise, with added benefits of muscle preservation and strength.
American Heart Association StudiesThe slow, controlled nature of HIT dramatically reduces injury risk compared to explosive lifting. Critical for maintaining long-term training consistency.
Sports Medicine Review, 2019Dr. Ellington Darden, Ph.D., spent over 40 years at Nautilus researching optimal strength training methods. His studies with thousands of subjects have proven the remarkable effectiveness of slow, high-intensity training.
Darden's signature protocol: 30 seconds negative, hold, 30 seconds positive. This extended time under tension (TUT) maximizes muscle fiber recruitment while minimizing joint stress. Studies show this produces superior results to conventional training in less time.
Darden's research confirmed muscles are 40% stronger during the eccentric (lowering) phase. By emphasizing slow negatives, you tap into untapped strength reserves and trigger greater muscle growth. The final eccentric to failure is the key growth stimulus.
In controlled 12-week studies, participants following Darden's HIT protocol averaged: 11.4 lbs of fat loss and 8.6 lbs of muscle gain simultaneously. Some subjects gained up to 18 lbs of muscle while losing 30+ lbs of fat.
Darden's studies included participants aged 18-80+. Older adults (50+) showed remarkable results, often gaining muscle faster than younger subjects due to years of untapped potential. It's never too late to build strength.
Darden's research definitively proved that one properly performed set to momentary muscular failure produces 90-95% of possible gains. Additional sets add fatigue without proportional benefit. Quality trumps quantity.
Darden's protocols require just 2-3 sessions per week, 20-30 minutes each. His research showed that more frequent training actually impedes progress by not allowing adequate recovery. Less truly is more.
High-Intensity Training was developed and refined by some of the most influential figures in strength training history:
Founder of Nautilus and MedX. Revolutionized strength training with his research on single-set training to failure. Trained hundreds of NFL teams and professional athletes.
Director of Research at Nautilus for 20 years. Author of 50+ books on HIT. His studies proved slow training effectiveness across all ages and fitness levels.
Mr. Universe winner who popularized Heavy Duty training. Proved HIT principles work for competitive bodybuilding at the highest level.
Modern HIT researcher and author. Refined slow training protocols for maximum safety. Trains clients worldwide using evidence-based HIT methods.
Each exercise follows a precise 5-phase protocol designed to maximize muscle stimulus while maintaining safety.
Get your weight ready and mentally prepare. The app counts down so you can focus.
Get into the eccentric (starting) position. Voice announces your countdown.
Slow, controlled lowering. Maximum muscle tension with minimal joint stress.
Powerful lifting phase. Maintain control and constant tension throughout.
Extended negative to complete muscular failure. This triggers maximum growth.
Voice-guided workouts that count for you. Focus entirely on the muscle contraction.
Real-time verbal coaching through every phase. Commander voice counts down and motivates you.
Built-in timer ensures perfect tempo. The app counts for you so you can focus on the contraction.
Log weights and track your strength gains over time. See your progress week after week.
Mark when you achieve true muscular failure - the key stimulus for growth.
Two complementary full-body routines. Alternate for balanced development.
Adjust phase durations to match your experience level and goals.
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