What makes Mountain Biking especially interesting in today's context is its minimal impact on local ecology. No emissions, no pollution -- mountain biking has to be one of the best ways to enjoy the hills without causing much ecological degradation.
All about mountain biking
Mountain Biking Gear
The type of Bike one buys is, obviously, important. Try several for fit and feel before settling on one. Biking enthusiasts usually recommend buying a true mountain bike, not a hybrid one (one way to tell is that true mountain bikes should come with fat, knobby tires). Here are some other things to bear in mind when choosing a bike --
- For a mountain bike to be the right fit, there must be at least two to four inches between the top of the frame and the rider's crotch. Any less room might be painful for the rider.
- When the rider reaches the handlebars, s/he should be able to bend at a 45 degree angle without feeling cramped.
- The saddle should be high enough so the rider's legs get almost fully extended when the pedal is at its lowest position.
- A bike with a front and rear suspension offers a smoother ride. This makes the ride a lot more comfortable and decreases fatigue. Even when buying a bike without suspension, it is always a good idea to get one in which suspension may be added later. 
The one thing riders can count on doing on their all terrain bikes, is falling off. Which makes a good helmet the second most important item on a Mountain Bike rider's wishlist. Here are tips on how to choose the right one –
- Try a few to get the right fit.
- Get one with plenty of air vents, or you will run the risk of frying your head on those hot days when you are going uphill!
- It makes sense to look for a helmet with a sun visor to keep the glare out of the eyes.
When buying a shirt to wear biking, remember that one which unzips down the front to let some air in, might be practical. Pockets on the back come in handy for storage. New fabrics which wick sweat away moisture are great. And get the loud neon colours – they look cool and can be spotted from a distance on trails so fellow riders can see you coming.
Good shorts provide support to the thighs and protect against saddle rash on the thighs. Most bikers wear traditional black racing pants made usually Nylon/Lycra mesh. Just ensure they have a good liner for saddle protection. Or else, they could just end up being a pain in the …you got the picture. Last, when looking for shoes, look for comfort (obviously) and cleats that click into the pedal. Veteran bikers say that these increase the biking experience ten fold, as the feet get locked in so they can't slip off the pedal.
How to do it
Correct posture while riding a bike is very important. Here are some tips on maintaining correct posture --
- Relax your elbows, keep them bent at about 90 degrees.
- Grip the bar firmly…if you see your knuckles turning white – you’re probably nervous and gripping too tight.
- Do not bend your back – keep it straight at about 45 degrees from the ground surface.
- Do not put all your weight on the seat. Get off your butt and try to transfer some weight to the pedals by standing on them.
- Remember to keep the pedals level when not pedaling.
The Skills Mountain Bikers Need
Mountain biking is all about balance, both left-right as well as front-back. Try shifting your weight for better traction – if for instance your back tire is slipping, shift more weight to the back, while if your front tire is rising up, move to the front to get your bike to settle down.
Climbing steep inclines requires both lung power and skill of the wheel. Don’t use very high gears while on an incline, it increases the chances of injury.
Bear in mind whilst descending, that you need to be as far back on your seat as you can. Brake well before you need to turn, you could easily spin out of control otherwise. Slow down to a safe speed, then accelerate out of corners. Also, if in doubt about the terrain or your ability, don’t be a hero – just get off the bike and walk. 
Braking efficiently and safely is a skill all mountain bikers need to learn. Use both brakes simultaneously – if you use just the back brake, the bike will skid. While skidding might look cool, it damages the trail and doesn’t slow you down efficiently.
The gears on your bike are to help you maintain an optimum pace. Pick the gear which enables you to keep to a speed of 60 and 90 rpm. Lower gears are easier to spin on hills, so try shifting to a lower gear when on a steep hill.
What can I do about it?
Be aware of the pitfalls on biking trails
- Steep inclines, sharp drops and narrow trails that one invariably finds on the more difficult trails, are certainly not for the faint hearted. Try to focus on the trail alone, not at what lies on either side of it.
- Mud and especially wet mud, is one of the worst things to ride on. Your bike will cause deep grooves which may result in erosion. Also the chances of slipping in it, or losing one’s control of the bike, are high. Don’t try and ride around it, though for this causes mountain trails to widen. If it is deep, walk. If it is shallow, pull up lightly on the bars, and either maintain speed or pedal through. 
- When you encounter a sandy patch, try using a higher gear for better traction.
- Rocks, holes, and bumps are part and parcel of mountain trails but terrible for your rear and back. Move your weight back so the front wheel rises up a little when going over rocks. If it gets too uncomfortable or risky, walk.
- Water and water crossings are dangerous, as one can not see what lies beneath the water's surface. Also, passing cycles will cause sedimentation of the stream. If there is no option but to cross a stream, remember to do so keeping a steady speed, low gear and a light hold on the handlebars.
- Watch out for dangerous conditions on or around the trail -- open mine shafts, cliffs, slippery or loose rock surfaces, etc. Never veer off the trail.
Learn the rules
The International Mountain Biking Association (IMBA), the international mountain biking organization, has set the following rules of the trail –
- Ride on open trails only – avoid trespassing on private land, respect trail and road closures and obtain permits and authorizations as may be required.
- Leave no trace – As with all forms of Eco Tourism, mountain bikers need to be sensitive to the trails they are on. Mountain trails often pass through ecologically sensitive areas. Cyclists may cause significant damage if they skid their tires too often, or if they ride through muddy trails.
- Control the bicycle! Mountain biking accidents can be quite severe, so make sure you obey speed laws. Alert other trail users well before approaching them and slow down or even stop when they pass. Be especially careful when turning corners. If an equestrian is approaching you, stop and get off your bike.
- Yield to Uphill Bike Traffic – that fellow huffing and puffing his way uphill always has the right of way. Stop and let him pass. Remember – you can get going easily, he can't!
- Never spook animals – some misguided bikers think it is a lark to sound their bell behind a peacefully grazing animal. But that can be foolhardy as well as silly – a scared animal is a huge danger to you as well as to others on the trail. Give animals extra room and time to adjust to you.
Tips on what to carry on a biking trip
Travel as light as possible on the bike, but here are some essentials that must find space in your backpack.
- Lots of water -- Cycling can make one feel parched pretty soon, and the breeze may actually make one's sweat and fluid loss to go unnoticed. Be sure to carry plenty of water with you when riding, and make it a habit to sip some fluid every 15 minutes. If it's going to be sunny and hot while cycling, also consider drinking at least 1 additional liter of water with rehydration salts mixed in. This helps muscles recover faster if you drink while riding.
- Snacks – dry fruit, granola bars, energy snacks and other low volume-high energy snacks are good. Easier substitutes include chocolate bars, bananas and glucose biscuits.
- First Aid Kit – Carry antiseptic cream, pain killers, muscle relaxant gels or sprays and bandages at the very minimum. One can be exposed to a lot of sun and dry weather cycling in the Upper Himalayan ranges - in these parts its essential to carry sun screen lotion higher than SPF 30 and vaseline or other moisturising lotions /lip balms.
- Basic Tool Kit – this should contain allen keys, screwdrivers, and, preferably, a chain breaker tool. Also carry a spare tube and a patch kit for punctures. Other tools you could carry are tire levers to remove and put back tires easily and extra chain links in case the chain breaks. Ideally you should carry a multifunction tool that is all of the above and more. It's compact and helps you save space when touring. Topeak's Alien range is generally regarded as the most popular.
- For those who do not have disc brakes and are going to travel more than a few hours in the mountains, never forget to carry spare brakes...they wear out pretty fast in the mountains.
- Cell phone or satellite phone, especially for those who ride alone.
Hot Tip: invest in panniers to hold stuff. Make your bike carry more if by using bungee cords to tie things to the carrying rack. Do not use backpacks as they strain the back.
Locating good cycling destinations
Mountain Bicycle Manufacturers
- Firefox bikes
- Reviews and ratings of mountain bikes available worldwide
- Trek Bikes International This is what Lance Armstrong rides!
- Commencal - The french cycle company, little known in the English speaking world, but great bikes!
- Specialized Another American manufacturer, marginally cheaper alternative to Trek.
- Thorn eXxp Perhaps one the best mountain bikes for touring rugged countries - costs more than what many can spare in a lifetime, but then again....this bike will outlast you, if not the rugged mountains it's mean to surmount.
See some mountain biking videos on YouTube and Google Videos. For more on how to position yourself on your mountain bike, go to [http://www.youtube.com/watch?v=vTfV85JbnwA YouTube