Suggestions for HIIT cardio

You could do 30 secs sprint, 10 secs rest on the treadmill. For the 10 secs, just hop off to the side. If you want to do 20 minutes, you could do this for 10 minutes at the beginning and then 10 minutes at the end of your workout.

You could do the same on a bike, but turn up the resistance to heavier, like you are pedaling through mud. I would do 20 seconds hard on the bike and 10 seconds medium-easy depending how you feel.

Also, any exercise in Tabata form is awesome! :-D

Pick 1-2 exercises (I only do this with one) and do 4 sets of 20 reps (at a slightly lower weight than what you'd select if going to failure). After each set, do a session of jump rope. Start out going for as many jumps as you can in 1-2 minutes based on your conditioning. After you finish jumping, go right back to your next set of your exercise.

Treat the whole thing as a giant super-set. Depending on how long your sets take, and how long you jump rope, you have a very effective HIIT session from 8-12+ minutes, without adding too much extra time to your workout.

I have worked up to 2 minute jump sessions and I range from 200-260 jumps. I add this to each of my workouts, and the extra challenge comes in the form of needing to push tired muscles associated with whatever training session you are doing. On shoulder and chest day, the challenge is keeping your arms rotating. On leg day the challenge is jumping. Every session cardio and breathing is at play.

Current exercises I superset this way include -

Push-Ups
Close-grip pull downs
DB walking lunges
Seated cable rows

One suggestion - if you add jump rope to your routine, spend the money and get a good speed jump rope. I ordered an RX jump rope sized and weighted to my specs and it makes all the difference -

http://www.rxsmartgear.com/black-ops/

Any suggestions for exercises (within the gym) that can be done for ~20 minutes of HIIT cardio? I've gotten these recommendations so far, but need more:

1. Treadmill: Walk at speed of 4 for 1 min, then hop off & do 5 burpees, get back on, repeat 10 times.

2. Treadmill: 5 minutes warm-up at speed of 4.5
2 minutes running at speed of 7
1 minute walking at speed of 5
2 minutes running at speed of 7

3. Stationary bike: 10-15 sec high intensity, 1 minute low intensity.

Thank you!

You dont even need to do the 2 minute iterations.

HIIT can be done with 30-60 sec all out sprints. Walk. Repeat.

I dont prefer treadmills.

I do mine at a track or a bike/walk/run path. Go all out for 30 seconds. Walk for 30. Repeat. In the beginning you dont even need to do that many reps as you are going as fast as you can.

Any suggestions for exercises (within the gym) that can be done for ~20 minutes of HIIT cardio? I've gotten these recommendations so far, but need more:

1. Treadmill: Walk at speed of 4 for 1 min, then hop off & do 5 burpees, get back on, repeat 10 times.

2. Treadmill: 5 minutes warm-up at speed of 4.5
2 minutes running at speed of 7
1 minute walking at speed of 5
2 minutes running at speed of 7

3. Stationary bike: 10-15 sec high intensity, 1 minute low intensity.

Thank you!

Treadmill is difficult for HITT, but the second option isn't bad although it's not good for somebody to say what speed you should be doing. Basically it would be 2-min (low intensity) / 2-min (moderate intensity) / 1-min max effort sprint; this might be easier on an elliptical, exercise bike, or on a track if you have access to one.

Exercise bike: 30-sec at or slightly above 110rpm's then 30-sec's planks or situps, rinse-repeat and do for at least 12-sets, build from there

6-sec sprints with 30-sec rest, rinse-repeat
1-min sprints, 2 to 3 min walk
Battle Ropes, 20-sec on / 20-sec off
Heavy Bag work. If you have an iphone or droid get a boxing "call-out" app and box for 5 min rounds (can shadow box too)

Especially if you have access to a track...

- run a 400-meter for time and give it a good effort, as if you were competing. Divide that time by 4 to get your 100-meter pace time. Multiply that time by 95% and run 100-meter sprints and try to beat that time every set. When you can, subtract another 5%.