Our generation has moved from walking and cycling to driving cars or two-wheelers, from field jobs to desk jobs and from a healthy diet to junk food. This Rapid Change in lifestyle in the past decade is the major cause for a rise in back and neck related problems in the current generation.
Walking is one of the simplest and the most sustainable form of exercise that can be done by people of all ages. Walking can lessen pain, hasten to heal, boost strength, increase flexibility and prevent further episodes of back pain.

1. Walking Improves flexibility and posture.

Your abdominal and lower back muscles play a vital role in maintaining the stability and movement of your lower back. A sedentary lifestyle can cause malalignment of the spine due to deconditioning and weakness of muscles supporting your spine. Over a period of time, the size and strength of your back muscles decrease leading to early fatigue, injury, and pain.
Decreased physical activity can cause the small blood vessels of your spine to become constricted, reducing blood flow to the spinal muscles. Walking helps open up the blood vessels, increasing the supply of oxygen and nutrients to these muscles which over time leads to an increase in strength and integrity of your lower back.
"Start out slow and easy and gradually build up your distance and then your speed,
Always walk on a flat surface with good footwear to prevent any injuries during a long walk. Walking on an uphill can force you to lean forward and strain the lower back.

2. Strengthens muscles in the feet, legs, hips, and torso

Lack of physical activity can cause the muscles and joints in your lower back and hips to become stiff. This stiffness creates increased pressure lower back (Lumbar Spine) altering its normal curvature
Walking increases your flexibility by stretching the muscles and ligaments in the back, legs, and buttocks. When you walk, specific muscles, such as your hamstrings, erector muscles of the spine, and hip flexor muscles are activated and stretched. The flexibility of your spinal ligaments and tendons is also increased, improving the overall range of motion in your lower back.

3. Strengthens bones and reduces bone density loss

Walking as little as three to five kilometres a week can help build your bone health.
Walking is a good weight-bearing exercise to maintain general health, cardiac health as well as bone health. The benefits gained in muscle strength and balance can reduce the risk of falls, a common cause of fractures in old age. Regular walking also helps in preventing osteoporosis (age-related weakness in bones) and can aid in reducing osteoarthritis (old age joint pains) pain.

4. Walking can help in controlling weight

Regular exercise routine helps maintain a healthy weight in all age groups. As we grow, the metabolism slows but walking helps in maintaining the weight with increasing age.
Walking does not only help increase the amount of energy you burn day-to-day, but it also helps you build more lean muscle.
Furthermore, participating in a regular, moderate-intensity exercise like walking can improve your mood, making you more likely to stay active in the long term.

Author's Bio: 

I am an Orthopedic Spine Surgeon in Jalandhar, Punjab for the past 3 years.
My special interest is to guide people about maintaining good spine health.