Are you ever totally comfortable on your bike? Strange to ask it but some people ride their whole life thinking discomfort is an inherent part of riding. Not so.
You can tweak things to help common complaints, although no-one would argue that some muscle aches, joint pain or numbness is likely to happen if you ride regularly, and for extended periods. Let's look at some everyday problems...
It's quite common for cyclists to get neck pain, headaches and or shoulder tension. The muscular tension is often due to handlebars being too low or the stem too long. This can be aggravated by adding aerobars that are too long, or just too extreme for your body to handle. Carrying heavy loads in a courier bag or haversack can put strain on the muscles around the neck and shoulders too. Worst still, this makes handling the bike precarious and lends itself to causing tension in the upper body long after the rider has got off the bike. Your shoulders and arms control your steering, braking and gear changing so it's a vital area to keep them working perfectly. Here's some tips:
Numbness in the forearms when using aerobars can be caused by a saddle that is not flat, too great a drop in height or compression of TT forearm pads.
If you do carry loads a rack and panniers help put the strain on the bike not you. It also allows better freedom of movement for the upper body - useful when looking backwards in traffic.
Always use gloves and if you have RSI-type symptoms look at buying some Specialized Bar Phat, or wrap two layers of bar tape.
Ever wondered why you feel heavy on your hands, the brake hoods cut into your hands and you always seem to be resting on straight arms? Enter common symptoms: Mr Tight Arms, Miss Blisters, Master Numb Hands and even Cmdr. Shoulder Tension. All because your saddle is not set right. A five minute job that could mean hours of pleasure, not pain.
You have to sit on a flat platform. Read that again. I am amazed at some saddle angles (>10 degrees downward tilt) and why riders miss the fact that everyone else has got a flat posterior platform. Get the saddle flat and many uncomfortable symptoms disappear.
One other area that can be worsened or caused by cycling is lower back pain.
This costs millions of pounds per year in the workplace and through NHS costs. In many cases a 'bad back' gets worse as time goes on and no intervention is used. So, lower back pain must be aggressively challenged. Your cycling has three possible causes: poor posture/position, riding big gears or poor flexibility. Add all of these together and you really are heading for a painful future. However the fixes for these are quite simple:
Use smaller gears and 'spin' - especially early in rides. It may mean starting out in a different direction if a steep hill faces you immediately outside the front door or warm up inside beforehand on rollers/ indoor trainer.
Build strength with sit up exercises and lower back strengthening, and take some time to stretch after you have ridden. Light stretching routine, holding for around 30-seconds can reduce those tight muscles. The winter is a good time to join a gym, get some instruction and spend some wet evenings 'pumping iron'.
Have a massage - yes it's not only the pro riders who can reap huge benefits from lower back, glute and leg massage.
Finally, but by no means having covered all areas of potential discomfort, we have the humble bicycle saddle. Saddles have been the least advanced technology in the past hundred years on the bicycle. Common complaints are hot spots, chaffing, boils, numbness or 'under-carriage' discomfort for several hours after riding. I would search out the saddle that best suits your backside by buying secondhand less than perfect versions (see eBay) and when you get one that you like buy new or nearly new versions. That way your back side has the same platform whatever bike you ride. If you only have the one bike the challenge just got a lot easier.
If your saddle is comfortable you sit on the bike properly, if you sit properly then, assuming the right reach to the bars, you will be able to handle the bike correctly. Most important weight distribution will be 60/40 (saddle/bars) and your shoulders, arms and hands will be comfortable. The best bike is the one that feels comfortable to you, not because it's a certain weight or has a certain brand name. Your bike must fit you and feel good - you can then get out the door with one less reason to come home early. Sadly I can't do anything about that long list of DIY jobs...
Think X, Y, Z
X is for examine: Know and check you bike dimensions periodically. Seats, seat posts, bars and brake hoods can all move with repeated use. If you know where they should be you'll never be guessing where your 'sweet spot' of comfort lies.
Y is for You: It may be that muscles, joint flexibility or the type of riding you do alters over time. Don't stick with the same position if your body or goals are different: the bike, like your training and aspirations, must adjust to suit your present (not past) needs.
Z is for ZZZ: Sleep is a time where brain and body get time to recharge, re-boot and recover. You can often spot comfort issues or overexertion from the way that you feel when you first get out of bed. If muscles don't appear to be liking your set-up it may be time to tweak something. Measure, move and monitor.