The horse is made ready for the day of battle, but victory rests with the Lord. - Proverbs 21:31
Getting ready and prepared is our part. Your preparation will look different depending on your life, it could mean sending out resumes, meal prepping, studying for a test, working out to prepare for an athletic event, or taking a class. The success of what we are doing is not dependent on our strength that is solely up to God and His will. Sometimes disappointment can follow, but we need to take a step back and look up to God and rest in His love. He can give victory to whomever He pleases and it does not always give victory to those who expect to win. Our role is to continue to strengthen our relationship with Him no matter the outcome. No matter the outcome of the last test, project, war or sporting event having God in our life is our true victory and safety.
Our strength and lifestyle can never measure up, but He is our victory and safety. He protected Daniel while he was in the lions den (Daniel 6), He can protect you from anything. It is still important for us to utilize our means and, “Not test the Lord your God” to force God to prove His power to save us from dangerous situations when knowingly unprepared (Matthew 4:7). An example would be jumping off of a building testing God to save you if He loved you; if you have the right gear, training, and equipment the same situation would not be testing God, as you would be prepared and ready. Things in this situation may go wrong and ultimately God will have a hand in keeping you safe and alive. In extreme circumstances of life and death, l personally find it easier to realize it is God, but His hand is in everything.
While you are trying to make daily changes to your life to be healthier you have a part to play, but ultimately it is in God's hand and it is only Him that can achieve the lasting change you desire. He works to change you your heart throughout the process and change your desires. God is all about changing you permanently, and getting to the root of the problem, which is where the real victory lies.