Certain reports say that strength training doesn't negatively impact performance. In fact, there are many benefits of building muscles and strength. When a proper weight training workout regime is followed along with regular runner's workout, it can prove very beneficial, here's why...
Why?
Running is a high impact sport, and due to the repetitive impact on the joints the possibility of injury is more. Strength training helps to minimize the occurrence of injury, by building muscles which support the joints. It also decreases the severity of injury when it occurs.
Power is a combination of force/strength of the stride and speed of the stride. General strength/weight training will increase the size of the muscle fibers, which will provide a base for explosive strength, prevent injury, and thus will lead to increase in power.
It helps to improve and maintain the steady oxygen levels of the body, which will help in running and jogging smoothly and effortlessly.
To increase speed while running, strength training indirectly helps as it builds strong knees and muscles. The natural long strides are a result of the strong forward knee drive, and a powerful push off.
How?
There is no particular way of training, but a combination of different kinds of weights should be used. There are some particular muscles which need to be focused on, while following a workout regime.
Start with a warm-up session of skipping with a jump rope with around 150 hits for 2 - 3 minutes. Then follow some cat and camel lower back movements, arm and leg rotations, squats, and curl-ups. It is very important that you follow the warm up exercises properly to prevent any muscle soreness or injuries during the workout. Make sure your warm-up lasts for minimum 10 minutes, before you start on the core exercises.
Stick to an intensity range which is between 50 - 70%, 1 RM. The work to rest ratio you need to follow is 1:1/ 1:2. For example, if one set of exercise takes 20 seconds, then rest for 20 - 40 seconds before you start the next set. Here is a sample workout comprising various exercises that you can follow.
Squats
Calf raises
Standing trunk twists
Standing horizontal pulls
Body wide straight-arm pull downs
Side bends
Standing leg curls
Hip adductions
Good-mornings
Forward raises with dumbbells
Triceps extensions
Bicep curls
Keep your breathing steady and deep while exercising, and perform stretching exercises to maintain a full range-of-motion of the joints. Along with these exercises include the cross training workouts like cycling, playing basketball, climbing stairs, and swimming. So, follow a healthy diet, balance out the exercises for cross training throughout your week, and achieve improved strength which will help you run better and faster.
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