What is better, burning calories on a bike or 20min cardio?

most times it is important to mix up your exercise routine just to prevent boredom and loss of interest in your goals. id suggest to incorporate whatever exercises make you want to get up and move and stay active.some other great options for cardio would be :jumping rope and its more efficient than cycling, try jogging,swimming,etc. aside from that, with as much cardio as you seem to be doing its probably time to get started in some body weight exercises and build up some muscle mass.such as push ups..lunges..squats..planks. after all muscle is what eats fat. cardio is well and good but the body will soon adapt to it (refer to metabolism) and youll find yourself having to do more and more of it to find the same results .plus youre not building much muscle throughout the body…limit the cardio to 3-5x per week.each session should be 30-45mins and about 160-200 minutes of it total per week. is more than adequate.also remember a healthy nutrional diet is a key to losing weight .a balance of fruits.vegetables. and lean meats. food can be your friend. as much as it can be your enemy . best wishes on your journey. and keep up the hard work.