In a two week study ( Short-term sprint interval versus traditional endurance training: similar initial adaptations in human skeletal muscle and exercise performance) researchers compared changes produced by sprint-inteval training (SIT) versus high volume endurance training (ET). Total training time 2.5 hours for SIT and 10.5 hours for ET, and total training volume was 90% lower for SIT versus ET
From the study: Brief, intense exercise training may induce metabolic and performance adaptations comparable to traditional endurance training....Given the large difference in training volume, these data demonstrate that SIT is a time-efficient strategy to induce rapid adaptations in skeletal muscle and exercise performance that are comparable to ET in young active men.
Brief, intense exercise training can be accomplished on aerobic equipment or by doing a series of strength training exercises. We can show you how to both at New Orleans Fitness Trainers and at Austin Personal Training Both are safe, effective, and efficient. You don't need to spend hours in the gym.