Generally yes, a single bout of high-intensity interval training tends to produce a larger acute growth hormone (HGH) response than an equivalent duration of steady-state cardio at a lower intensity, primarily because GH release is strongly tied to exercise intensity rather than exercise duration alone. One study found that seven one-minute bouts of intermittent high-intensity cycling significantly elevated GH concentrations above those seen during 20 minutes of continuous cycling at a lower, steady wattage (PMC).
Why Intensity Drives the GH Response
Growth hormone release during exercise is closely linked to the buildup of metabolic byproducts like lactate, which tends to happen once exercise intensity crosses above the lactate threshold. Below that threshold, GH secretion tends to rise only modestly, but once exercise intensity pushes past it, GH output climbs sharply. This is a big part of why HIIT, which by design pushes the body repeatedly above that threshold during the work intervals, tends to elicit a stronger GH response than steady-state cardio performed comfortably below it. One older study even found that a single 30-second bout of maximal treadmill exercise increased GH concentrations tenfold above baseline an hour after exercise, illustrating just how sensitive the GH response is to very high effort.
The Nuance: It Is About Intensity, Not the HIIT Label Itself
It is worth being precise here, because the research does not suggest something magical about interval structure specifically. Rather, it is the intensity achieved during the effort that matters most. A pilot study directly comparing an acute bout of high-intensity interval exercise to moderate-intensity continuous exercise found that the interval protocol extended elevated GH secretion over a 12.5-hour window, supporting the idea that harder efforts produce a more robust and longer-lasting hormonal response than comparable moderate-intensity continuous sessions. If someone pushed a steady-state effort hard enough to reach similar intensity, the GH response would likely be comparable, but by definition steady-state cardio is usually performed at a lower, more sustainable intensity, which is precisely why it tends to produce a smaller GH bump.
Does Training Regularly With HIIT Amplify This Over Time?
Here the evidence gets more mixed, and this is an important distinction between an acute response and a training adaptation. A controlled study in sedentary men found that four weeks of high-intensity interval training did not enhance the exercise-induced GH response compared to before training began, and a low-intensity continuous training group showed the same lack of improvement (PMC). In other words, while a single HIIT session tends to produce a bigger acute GH spike than a single steady-state session, simply doing more HIIT over time does not appear to make that per-session GH response grow larger. The acute advantage of HIIT seems to hold up fairly consistently, but it does not compound with training the way some might expect.
Practical Takeaways
For men choosing between HIIT and steady-state cardio with GH optimization specifically in mind, the research suggests HIIT has a modest edge for any single session, largely because it is easier to reach and sustain the higher intensities that drive a stronger GH response. That said, GH release is only one small piece of the broader picture. Steady-state cardio has its own well-established benefits for cardiovascular health and recovery capacity, and the acute GH bump from a hard interval session, while real, is not itself a guarantee of better long-term body composition or muscle outcomes. The most practical approach for most men is to include both types of training rather than picking one purely for its hormonal effect.