2.3. Procedures
This study was conducted at the Ishizaka Golf Club at Hatoyama, Hiki-gun, Saitama, Japan. The study was performed between February and March 2022. Participants were required to abstain from consuming alcohol during the evening before each round and to come to the venue without breakfast on each test day. The participants were required to report to the clubhouse 30 min before their scheduled start time. Thereafter, the participants consumed a standardized breakfast served at Ishizaka Golf Club in the starting order. During both trials, a standardized breakfast (635 kcal: 12% protein, 25.1% fat, and 48.3% carbohydrates), which consisted of rice, miso soup, salted salmon, natto, and boiled egg, was consumed between 8:00 a.m. and 8:30 a.m. on the experiment day. The energy and nutritional intake of breakfast were calculated by a dietitian using the weighing method. Nutritional intake was estimated using Eiyou-plus version 1 (Kenpakusha Co., Ltd., Tokyo, Japan) with the Standard Tables of Food Composition in Japan, 2020 Edition (8th Revision). The ACSM guidelines recommend 1–4 g bodyweight (BW) (intake per kg of BW) of carbohydrates 1–4 h before exercise [In this study, gummies (Fettuccine Gummi, Bourbon Corporation, Niigata, Japan) were used as the test food during the golf round. In Japan, gummies are commonly distributed and readily available food; in addition, it is rich in carbohydrates. Thus, in this study, we considered gummies to be a suitable food for competitive golfers in terms of real-life applications. The recommended carbohydrate intake in endurance competitions is 30–60 g per h [All participants used the same equipment (golf clubs and balls) during the two rounds. During the round, the participants carried their golf equipment in a cart and walked. The scores were tallied during the round. A putting performance test was conducted at the end of the play on each hole. Driving performances were conducted before the start, after the 9th holes, and after the 18th holes. Cognitive performance was conducted every three holes (before start and after 3th, 6th, 9th, 12th, 15th, and 18th holes).