Isaiah 40:29-31

29 He gives power to the faint and increases the strength of the weak. 30 Even youths grow tired and weary, and young men stumble and fall. 31 But those who wait upon the LORD will renew their strength; they will mount up with wings like eagles; they will run and not grow weary, they will walk and not faint.

amp 29 ^He gives power to the faint and weary, and to him who has no might He increases strength [causing it to multiply and making it to abound].

30 ^Even youths shall faint and be weary, and [selected] young men shall feebly stumble and fall exhausted;

31 ^But those who wait for the Lord [who expect, look for, and hope in Him] shall change and renew their strength and power; they shall lift their wings and mount up [close to God] as eagles [mount up to the sun]; they shall run and not be weary, they shall walk and not faint or become tired.