The past few years High Intensity Interval Training has been my go to workout of choice. Basically HIIT is simply going at it very hard for short durations with very short breaks in between. This approach quickly raises your heart rate to the max zone!
Why HIIT? Lots of reasons... for starters a single session can be done in about 7 minutes! With all the benefits (and more) of 30 mins sustained cardio exercise. On a good day I will do 3-4 rounds so around 30 minutes of exercise, but if I am short on time one single round is fine! Also I am no gym rat... in fact I do not have a gym membership and strongly prefer the flexibility of doing my exercise ANYWHERE. Simple is good, you do not need tons of equipment. I use a speed rope and kettlebells... and even the kettlebells are optional. I dump the bells when traveling and simply do old school body weight exercises such as push ups, pull ups, planks, dips etc.
Not only can an HIIT workout be completed in 7 minutes... it is also something I only need to do 2-3 times a week.. and most weeks only twice! I still do some normal aerobic training during the week in the form of walk, jogging or biking... this is the type of activity where my breathing is slightly elevated but I can carry on a spoken conversation without any problems.
Here is the short equipment list I use-
25lb kettle bells (you really only need 1 kettle) Mine is an AmazonBasics... I only see the 20lb listed now though- https://amzn.to/2CJ8rNA
My speed rope jumprope- https://amzn.to/3hg1wdS
To make for strong feet I like to workout in New Balance minimum trail runners- https://amzn.to/32fZNz4
If you want to learn more about the benefits of HIIT and who should be doing it check out this video- https://youtu.be/guzDr-7UgYY
Also I will drop a video here from my HIIT session yesterday which was a full 30 minute endeavor! Just remember you can do this in 7 minutes and get amazing results. You do not need tons of equipment or spare time! 7 minutes!!!