Consistency is good, but monotony is not. If you've settled into the same old weekly workout plan, chances are your body has adapted and you've reached a performance plateau.
This might not matter to you if you're more interested in sticking to a plan than improving your fitness or performance. However, if you're struggling to improve your triathlon performance, it might be time to switch things up.
You must change your normal routine to get an adaptive response from your body.
Change the Order of Long Weekend Workouts
Triathletes with a Monday-through-Friday work schedule often do long workouts on the weekend. Depending on personal preference and family obligations, many people will do a long ride on Saturdays and a long run on Sundays. This routine gives the feeling of running on legs that are fatigued from a long ride the day before. Running fast (relative to race distance) on tired legs is a skill that the best triathletes develop.
If this is your usual routine, try switching the order. Try doing a long run Saturday and a long ride on Sunday. Pay close attention to your run pace. Can you keep a higher average pace on Saturdays, compared to your normal Sunday long run, for the same heart rate cost?
Put All the Quality in One Sport
If your weekly plan has one speed workout in each sport, try putting all of the quality work into a single sport. For example, make swimming and running workouts completely aerobic and put all of your intensity or interval work into two or three bike workouts.
Be certain you're rested for those quality workouts so you can produce the best possible power or speed for your goal intensity in that training period. If you try this method, focus on one of the other sports in subsequent weeks.