40 is young to be having this problem with your lifestyle......
Testosterone:
Running and walking do not help erections. Lifting weights and doing compound movements like bench-presses and squats do.
High protein diets do not help testosterone, but diets with fats in them cause testosterone to increase....For your choice of fat, use fish oil of which I take some 7 to 9 pills daily for erections.
Nerves: release NO
B-100, vitamin k2, vitamin e, and magnesium
Blood flow:
cayenne, fish oil, magnesium, vitamin c
muscle tone at base of penis:
vitamin c, magnesium
Having and maintaining an erection is complex: you testosterone, nerves must function properly to release NO which initiates the blood to enter.
Good luck and hope you don't have a sugar problem. If you don't have a sugar problem, then consider doing everything to reduce cortisol so go to wikipedia and search cortisol......You'll need time-release vitamin c and consume some 5 grams daily!
Sounds like your system could do with a boost, and these should help boost your erections, there simple and not drugs,
Tribulus will help your libido, help your testosterone and boost your energy, and take around 8 weeks to get up to full power, then there is Cayenne, Garlic and Ginger, these 3 will help your blood flow down below, Cayenne I take in tomato paste with olive oil to thin it down and take 3 small spoonfuls 3 times a day, Garlic chop the cloves from a whole head and put in olive oil and take as above, but on alternate days, and Ginger I take this in black tea with lemon and honey, but you can use green tea as well, you can either use fresh Ginger or dried powder, OK first you can google all these for more info and just add for ED on the end, try to let us know how you get on.
Good Luck
thank you, i will be seeing a doctor for a checkup in the next few weeks.
Get checked for diabetes. That's one of the most common causes. The other is vascular problems. Eat a heathier diet. Do not smoke. Take L-argimine.