Your Body, Yourself
As crazy as it sounds, many guys experience sympathetic pregnancy aches and pains right along with their partners (this is called Couvade's syndrome). This empathetic experience may include, among other things, a hearty weight gain. And often after the birth of Baby, parents experience even more weight gain, in part because they are sleeping less, are stressed out, and subsequently don't eat and exercise as healthfully or regularly.
Remember, pregnancy lasts for nine months—you've got time to get prepared. Before your life becomes too hectic, begin eating and living healthier in preparation for your baby's arrival. Establishing healthy lifestyle habits now will give you a better chance of maintaining some of those habits after Baby comes. For instance, you can take a walk with your partner, a stroll through the neighborhood after dinner. Not only will that be good exercise for you both, but it will be nice time where you can catch up on all that is going on with each of you, building your connection even stronger for when Baby arrives. If you haven't historically helped with meals, this is a good time to begin to participate more by making sure more vegetables and other healthy food make their way onto the table. This will be invaluable when things get a little crazy after your baby is born.
Because, of course, your partner's health is vital; she's carrying and supporting your baby, but your own health is crucial, too! You need your strength just like she does. Think of this as your own Spring Training: You need to practice now so when Baby comes you will be in great shape for the real thing.