When someone says you will burn more fat in the «fat burning» zone you tend to believe them because it sounds scientific, but Visual
Impact Cardio shows you it's also possible to burn a lot of fat while performing HIIT.
The research data on concurrent endurance and strength training
shows that moderate amounts of
cardio training, on the order of 3 days per week + / - 1 day for 30 minutes + / - 10 minutes, will have little or no negative
impact on strength or muscle gains.