HIIT, LISS, Running — How to Train Your Heart and Burn Fat Most Effectively
LISS is low-intensity steady-state cardio, performed at 50-65% of maximum heart rate. This is walking, light running, cycling, swimming at an easy pace. LISS lasts longer (30-90 min.) but is gentler on the body.
Does not increase cortisol levels, is suitable for active recovery, improves fat oxidation, is safe for joints, does not require long recovery, can be performed daily.
| Criterion | HIIT | LISS |
|---|---|---|
| ✅ Duration | 10-25 min. | 30-90 min. |
| ✅ Calories per Minute | 10-15 kcal | 5-8 kcal |
| ✅ Afterburn effect | Up to 24 hours | Minimal |
| ✅ Muscle preservation | Better | Intermediate |
| ✅ Cortisol effect | High | Low |
| ✅ Suitable for daily use | ⚠️ No (2-3x/week) | ✅ Yes |
One 20 min. HIIT workout can increase metabolism for 24 hours after the workout — the so-called "afterburn" (EPOC) effect.
The highest percentage of fat is burned in the 60-70% max HR zone (LISS), but HIIT burns more total calories.
L-carnitine + cardio = a powerful combination for fat burning. L-carnitine helps transport fatty acids into the mitochondria.
For health maintenance — 150 min. of moderate-intensity or 75 min. of high-intensity cardio per week (WHO recommendation). For weight loss — 200-300 min. per week.
LISS can be done every day. HIIT is recommended no more than 2-3 times per week so the body has time to recover.
Both options work. Morning cardio can help build a healthy routine, evening cardio can reduce stress after the workday. The most important thing is consistency.
Running burns more calories per minute, but cycling is gentler on the joints. Best is to combine both.