High Intensity Interval Training Tips | Top 3 HIIT Cardio Mistakes- Thomas DeLauer… Correct Ratio: When HIIT workouts were first developed, they were super-quick, seven- to 10-minute routines designed so that you could perform your chosen form of cardio at maximum effort. True HIIT is like sprinting (should make you feel like your gas tank is completely empty) - if you’re doing a 30-second sprint during a HIIT interval, you shouldn’t be able to get to second 31 without wanting to collapse. Which means: If you’re able to go for even a second longer then you probably didn’t go hard enough. HIIT should be performed with at least a 1:2 work/rest ratio, but in most cases, it should actually be performed with a 1 to 3 or 1 to 4 work/rest ratio. If you do a 30-second interval and then only rest for 20 or 30 seconds, there is very little chance that you can perform the intervals at 100% intensity.
Plyometrics: The term plyometrics stems from the Greek words "more" and "measure," which we've appropriately translated to more power. Plyometrics in simple terms means jump training and it enhances our explosiveness, power, and body control - its purpose is to increase muscular power and dynamic strength. Examples are: Squat jumps, box jumps and kickboxing kicks - high intensity exercises that burn fat and train your fast-twitch muscle fibers that are beneficial for speed and power.
Plyometrics Physiology: Plyometric exercises help increase the body’s ability to rapidly contract their muscles after they have been partially stretched - this is called the stretch shortening cycle. Specifically, the way in which plyometric exercises increase muscular power utilizes the natural elasticity of the muscle and tendon, as well as the stretch reflex. Following the eccentric, landing phase, with an immediate concentric contraction (such as jumping up again), causes the stored energy to be released - this increases the total force produced. The stretch reflex is the body’s response to a muscular stretch - this response, which is involuntary, is initiated by the muscle spindles (stretch receptor organs within a muscle.) The muscle spindles detect the speed and intensity of a stretch and so during plyometrics, detect the rapid stretching of the quads (when landing.) Their response is to protect the muscle from over stretching by increasing the activity of the quads (the agonist muscles) and so the force the muscles produce. Plyometric activities can be broken down into three parts:
Therefore, the subsequent concentric contraction must occur as soon after the eccentric phase as possible, to get the most benefit from the exercise. With training and proper progression, plyometrics have shown to markedly increase overall strength and power.
Study - Published in the journal of Applied Physiology Nutrition and Metabolism: The aim of the study was to compare the effects of 12 weeks of high-intensity interval training (HIIT) with the effects of 12 weeks of plyometric exercise combined with HIIT (P+HIIT)
68 participants were assigned to 1 of 3 groups: HIIT; Plyometrics and HIIT (same HIIT program as the first group); or control (no exercise)
Taken together, these findings suggest that adding plyometric exercises to a HIIT program may be more beneficial than HIIT alone in obese female adolescents.
Upper Body HIIT: Study - Brazilian Journal of Physical Therapy: Looked at the cardiac autonomic responses during upper versus lower limb resistance exercise in healthy elderly men.
Design: Ten volunteers underwent the one-repetition maximum (1RM) test to determine the maximum load for the bench press and the leg press. Discontinuous RE was initiated at a load of 10% 1RM with subsequent increases of 10% until 30% 1RM, followed by increases of 5% 1RM until exhaustion.
Results: Parasympathetic indices decreased significantly in both exercises from 30% 1RM compared to rest and HR increased (69 to 90 bpm for upper and 66 to 89 bpm for lower)
Cardiac autonomic change occurred from 30% of 1RM regardless of RE limb - however, there was more pronounced sympathetic increase and vagal decrease for upper limb exercise than for lower limb exercise. Why This Is: Upper limb RE generates different cardiovascular responses compared to lower limb exercise. In addition, upper limb exercise also induces greater perceived exertion compared to leg exercise at the same relative workload.
Peripheral Vascular Resistance & Hemodynamic Demand: As mentioned, upper and lower body exercise produce significantly different blood pressure and heart rate values at similar cardiac outputs. Blood pressure is increased with upper limb exercise since the muscle contractions increase the peripheral vascular resistance to a greater degree than what is found in lower limb muscle contraction.
