Your endurance training should ideally not mess with your strength training.

1. If you are targeting neural adaptations (below 5 reps), it is always a good idea to start the workout fresh. What you do afterwards in terms of endurance is not that important.
2. If you are targeting hypertrophy, it is best to give your body some time afterwards to recover (ideally 40+ hours). You can actually arrive a bit fatigued for the workout. It depends on your goals, training intensity, and recovery capacity. Here are some general guidelines:

• Same Day (6+ hours apart): If you must do both on the same day, try to separate them by at least 6 hours, prioritizing hypertrophy first and endurance later.
• Next Day: If your endurance training is low to moderate intensity (e.g., Zone 2 running or cycling), doing it the next day is usually fine.
• 48 Hours: For high-intensity endurance (e.g., sprint intervals or long-distance runs), waiting at least 48 hours can help preserve muscle growth and prevent excessive fatigue.
• If your goal is maximizing hypertrophy, limit endurance volume and avoid excessive cardio that interferes with muscle recovery. If your goal is balanced fitness, manage intensity and nutrition to support both adaptations.