I'm discouraged about weight loss. I took my doctors advice and bought a stationary bike for Christmas. I have been riding it 20 minutes a day since then and instead of losing weight, I have actually gained 3 pounds.
I got the bike because walking is hard for me but I am still able to pedal a bike. I'm 67 and have been diabetic since my early 20's (I was not overweight then or at anytime earlier in my life). I have not changed my eating habits since riding the bike, if anything I have tried to lower my calorie intake.
You might need to try tweaking your 20 minute routine to get a better burn.
Try this....pedal normally for 5 minutes. Then, for the next ten minutes, alternate with normal pedaling for 30 seconds, and then speed up for 30 seconds...then, increase the tension if you can for three minutes, and cool down with two minutes. See how this helps.
Also, try going to www.MyFitnessPal.com and log in what you eat each day, and see how you stack up with calories, fat, carbs, and sodium. Sometimes, too much sodium can make you retain weight...By logging your meals, you might be able to find some areas that you haven't noticed before... You can also log in your exercise, and it will give you an idea about how many calories you are burning. A moderate setting on a stationary bike burns about 170 calories. In order to lose weight, you have to burn about 500 calories a day more than you need! So, if you are burning 170 on the bike, then you will need to decrease about 230 calories a day from your amount you ate before you started to exercise.
It is a numbers game when losing...The program I suggested above is FREE and will help you to manage those numbers. It also has FREE apps for Android phones, as well as for iPhones, and iPads. I love the camera feature which allows you to scan the label of a food, and it instantly adds the food and ALL its nutritional values in...so easy. You can also use the recipe feature, and the saved food/meals to be able to quickly enter foods/meals you use a lot.
I hope these hints help.