You're Correct!

If you find that in the middle of your golf round you tend to have a few holes either just before the turn, or just after the turn, where you do not score as well and it is consistently in those areas on your round, then one of the things that is happening is that you are losing focus and concentration in that area and this can be due to the fact that you are not eating and drinking as you are playing.

If you wait until the turn, until between the 9th green and 10th tee before you do eat and drink when you are out playing, you will have already become dehydrated and hungry. When this happens you lose your focus and concentration and as a result of this, your play will deteriorate. As you start down the first, your energy levels are high but you are using your energy as you are playing. By the time you get to the seventh green and you are now approaching the eighth tee and you have not replaced any of that energy or liquid that you have been using as you have been playing, your concentration and your focus will deteriorate.

Rather than waiting until you are on the back nine or you are at the half way point before you eat and drink, make sure that you graze and snack more through the round. Make sure that you have got plenty of liquid with you, water is ideal, or water and cordial, or an isotonic drink. Make sure that you have plenty of food to snack on as well, muesli bars, nuts, fruit, that type of thing, where you can replace your energy and do that from the first hole.

Work on drinking on one hole and then eating on hole two. Have a few sips of drink on the first hole and then on the next hole just a few nibbles on the fruit, or muesli bar, or whatever it is you are grazing on. This will help you to keep your energy levels more constant rather than waiting until you have dropped your energy levels on the eighth or the ninth hole and then you are having to refuel from a very low energy level. This will mean that it then takes several holes to get the energy into your system and so by the time you are on eleven and twelve, you have got your energy levels back up.

Work on grazing throughout the round to keep your energy levels constant, especially on the front nine, before you get to the turn rather than waiting until you are hungry and thirsty at the turn on the ninth and the tenth.

Your swing is not altering, you are still technically making the same movement. Your mechanics do not change, but your attention levels and relaxation levels do. It is not necessarily that your swing has changed. If you have lost your swing it is more to do with the fact that you have lost your concentration. Work on eating and drinking to maintain that.

You need to have a practise swing before you play the shot, you need to make a rehearsal of what you are about to do.

Rather than thinking that this is wasting energy, it is absolutely crucial to help you execute the shot that is required. Make sure you have a practise swing before you play every shot, a minimum of one.