1 Timothy 4:8 (AMP)
For physical training is of some value (useful for a little), but godliness (spiritual training) is useful and of value in everything and in every way, for it holds promise for the present life and also for the life which is to come.

Exercise is the exertion for the sake of training or improvement whether physical, intellectual, or moral; a practice to acquire skill, knowledge, virtue, perfectness, and grace. Exercise is bodily activity for the sake of keeping the organs functioning in a healthy state.
Exercise is synonymous with the gym, health spas, all types of weight loss ideas and keep fit programmes.
We take so much delight, pride, and discipline in maintaining our looks, and shapes, we pay an obscene amount for keep fit activities and gym that we sometimes don’t even use.
But 1 Timothy 4:7 says to exercise yourself unto godliness, exercise unto godliness depends on the exercise of the spirit, where the Lord is. If you are going to exercise yourself unto godliness, you must know how to exercise your spirit because God is in your spirit.
Consider how we can exercise our spirits for you to turn on the spiritual switch to start building and strengthening your spiritual muscles.
We can exercise our spirit by prayer.
When a person walks, he exercises the feet. Before a child learns to walk, he must first learn to crawl.
I expect there are Christians who do not pray either because they don’t know how or don’t think it’s necessary to their Christian growth, some pray by considering something in their mind as a wish.
We must consider the way we pray. The exercise of prayer is not one of futility but a chance to partner with eternal matters, failing to exercise our spirit in prayer will cause the leanest of spiritual muscles.
We know we have many organs that function to do certain things. The ears are for hearing, the eyes for seeing, and the tongue for tasting, the hands for touching, and the feet for walking.
If we are going to think, to consider, we must do it by our minds, but we must realize that prayer is something different from all other things. We pray by exercising our spirit.
Our body functions physically and emotionally daily and for us to reach our peak performance, we must train ourselves mentally as well.
Our spirit is the fuel that runs our body and needs a different kind of exercise to help us perform to peak performance. Each type of exercise will test our will and there will be times when part of us wants to stop and quit already, especially in the face of adversity, afflictions and pain but we must keep going, you know what they say-“no pain, no gain.” So, no spiritual exercise, no spiritual gain.
Every Christian matures in their body and their mind or soul (mind, will, emotions, intellect, imagination) as they also mature spiritually by exercising their spiritual senses.
If a limited physical exercise is beneficial to the performance of the body, think how much beneficial gain there is in exercising the spirit through the unction of the Holy Ghost?
Exercise the spirit in fasting, prayer, bible study, worship and fellowship with other believers who will encourage and motivate you to grow.
Dieting without physical activities isn’t so gainful, dieting your spirit will not benefit you, do not neglect your spirit, exercise it or you’ll end up with spiritual malnutrition. Exercise your spirit.
Shalom