Being able to train consistently with minimal interruptions requires staying healthy, above all. Doing what you can to avoid illness in the first place is important, but so is adequate sleep and nutrition. Sleep is essential for recovery including growth and repair of cells, metabolism, and immune function. Further, there are some associations between diet and healthy sleep.
Daily Energy Intake
Energy restriction or low energy intake relative to training can reduce sleep quality and increase wake episodes. Avoid calorie deficiency, particularly during periods of intensified training and ensure adequate post-workout recovery with prompt refueling and rehydrating.
Daily Protein Intake
Diets higher in protein appear to be associated with improved sleep quality and fewer wake episodes. Eat adequate protein in the range of ~1.6-2 grams per kilogram of body weight each day.
Daily Carbohydrate Intake
Diets higher in carbohydrate appear to be associated with reduced time to fall asleep. Ensure carbohydrate availability around training and avoid doing fasted training. Additionally, a higher glycemic carbohydrate snack (such as cereal, rice, a potato, etc.) 1-4 hours before sleep may also improve sleep quality and reduce wake episodes.
Interestingly, high-fat diets may negatively impact total sleep time.
Sleep Hygiene
Athletes do appear to be prone to sleep disturbances, for reasons such as early morning or late evening training times, caffeine use, and screen time, including social media and virtual training. Reducing these sleep disruptors much as possible, especially in the hours before bedtime is important. Taking steps to schedule at least eight hours of sleep is also key. If needed, scheduled daytime naps can also contribute to overall sleep needs, but avoid napping immediately prior to training.
Supplements
Provided good sleep hygiene practices are being followed, there are a few supplements that may help to promote sleep. Tart cherry juice, which contains the sleep promoting phytochemical melatonin, may help improve sleep time and quality when taken for two weeks. A tryptophan dose of one gram can also improve time to onset of sleep and reduce wake episodes. Micronutrients including magnesium, iron, and zinc also appear to be associated with longer sleep duration by helping to regulate sleep cycles in the brain.
Before resorting to supplements, my advice is to lean into the basics. As your training load ramps up, take additional care to get in additional nutrients and energy...and evaluate where you can improve your sleep schedule and environment.