Mid-distance Swimming and Diet

Keep_The_Laughter

Are there any swimmers/triathletes out there who would like to give a bit of advice? I'm considering entering a gym challenge to swim 52,000 meters in 20 days. In order to complete the challenge and maintain my anaerobic workout schedule, I'd have to increase my average swim by 700 to 800 meters. My main concern is avoiding fatigue and post swim cramping during the first week of the challenge.

With the nutrition listed below I have not had any cramping or fatigue swimming 14,000 to 15,000 meters a week.

One hour pre-work out:
120-135g plain 2% greek yoghurt
1 serving raw nuts
1 serving of berries or grapes
15-20g chia seed and oat granola

Within 20 minutes post-workout 1 liter of homemade energy drink:
150-200 ml of mixed kale and fruit juice
800-850 ml of water.

Would any swimmers/triathletes like to give me their opinion on whether this regimen seems on target for a 4000 to 5000 meter weekly increase? Or if anyone out there has other suggestions, I'd be interested to know what is working for others. Thanks in advance.