Try this TRX (HIIT) high intensity interval workout from inventor of the Rip Trainer Pete Holman and STACK.
 

If you are looking for the most effective way to achieve your fitness goals, you need to try high-intensity interval training (HIIT). HIIT workouts are a proven way to improve endurance, burn more fat faster and minimize training time, while still increasing strength and power.

HIIT workouts involve performing exercises at maximum intensity for short durations followed by limited rest intervals. Each rep should be intense, rating at least an eight out of 10 on a perceived scale of exertion. If you aren't out of breath and gassed after a complete circuit, you are not working hard enough.

Performing the following TRX Rip Trainer HIIT circuit will "hit" every muscle in your body while targeting critical aspects of performance, including strength, balance, power, endurance and mental focus. Although intensity is important during HIIT training, attempt to progress to faster and more powerful movements, and never sacrifice control for intensity.

Rip Windmill
This exercise will load your core by activating your abdominals, hips, low back and scapular muscles. Developing these muscles will improve your posture, balance and power transfer and reduce the risk of back injury. In addition, performing this exercise at a high speed offers a tremendous metabolic challenge that will improve your overall endurance and increase fat burn.

• Stand sideways to the anchor point using an alternating grip
• Draw circles with the end of the Rip Trainer, while squatting up and down
• Perform for 30 seconds at high speed, rest for 15 seconds and proceed to the next exercise

Rip Kayak
The Rip Kayak develops your posterior chain (muscles in the back of your body) in an offset foot position to challenge your balance. This will increase pulling power in a balanced position, while still challenging your heart and lungs.
 

• Stand in an offset stance facing the anchor point with an alternating grip, as if holding an oar
• Pull the Rip Trainer back and return to start position in an arching path, as if rowing
• Focus on pulling your shoulder blades back and follow the same path each rep
• Don't let the cord hit the side of your leg
• Perform for 30 seconds at high speed, rest for 15 seconds and proceed to the next exercise

Rip 90-Degree Jump Press
This exercise is about speed, power and agility. It mimics an Olympic-style lift, but it adds a rotational component to challenge your core. It should be performed with max effort each rep while maintaining a wide, stable base and using perfect technique. Be prepared to be gassed after this exercise.
 

• Stand with the anchor point to your side
• Hold the Rip Trainer at your chest with an overhand grip
• Jump 90 degrees away from anchor point and aggressively press the bar off your chest
• Perform for 30 seconds at high speed, rest for 30 to 60 seconds and repeat the circuit on the opposite side

If you haven't purchased your TRX Rip Trainer, get it here.