How to Get the Most out of your Build Phase

With spring just around the corner most people following a periodization plan will be starting their build phases in the next month or so. We’ve already covered some of the basics of the base phase in a previous post and today we’ll go into some detail about how to get the most out of the build phase. For some the build phase can be a daunting and uncertain period of training. Base training is relatively straight-forward. It requires a lot of aerobic endurance training which is the sort of riding we tend to naturally do when we go for a ride. The build phase, however, requires more focus on specific systems and the types of workouts vary greatly. In this phase the primary objective is to maximize aerobic power and start building the top end. Anaerobic endurance and VO2 max intervals are a staple of this period and it’s important to get the timing of these workouts right. While it takes a long time to build a solid base –there’s almost no such as too much base–¬†building top end power only takes a short amount of time and can fizzle out quickly if incorrectly planned. The last thing you want to do is hit your peak top end power 2 weeks before your critical race.

Because top end power takes less time to build and takes a greater toll on the body in terms of effort and fatigue, the build phase is typically much shorter than the base phase. Only about two build cycles are needed to develop maximum top end power. It is important therefore to remember that everyone has a physiological peak for top end power. This means that adding a third or fourth build cycle will not necessarily equate to greater top end power. Eventually top end power will start to drop off (top end fitness falls off as quickly as it comes in most cases). It is possible to increase the physiological peak of your top end power until you hit your true absolute physiological potential but it takes several cycles over several race seasons. If your plan calls for two peaks in a season, you might find your top end power increases in the second peak. The point to note here is that two build cycles is about enough to hit your peak. If you want to increase your top end power further, it’s necessary to take a week or two to recover fully and detrain your top end power a little (I know that sounds terrible but it’s necessary) and then begin to build back up again. We’ll go over this more extensively below.

How to Plan a Build Phase

The First Build Cycle

The build phase should begin at the end of a strong and solid base phase. Very rarely is it beneficial or recommended to try to jump back into a build phase from the previous season’s peak. Allow your body some off season unstructured detraining time and then start a new base phase to begin building fitness again. Building fitness each year is like building a structure made of blocks. Every year you want to increase the height of the structure, which means widening the base. Detraining requires dismantling some of the base so that you can incorporate more blocks to make a larger base for a greater height. The base phase rebuilds the base of the structure making use of the new blocks and the build phase is when you start building upwards. The build phase can only be effective if there is a solid base built to withstand the higher loads and efforts of the build phase.

By the beginning of the build phase you should have already begun to incorporate some elements of build training into your last base cycle. This last base cycle should have one VO2 max workout which includes 3, 5, and 8 minute VO2 intervals. It’s also beneficial to start incorporating short 30s to 1min anaerobic efforts to the end of each 12-20min interval during sweet spot/tempo/threshold workouts. This will help prep the body for harder efforts during the build phase.

It’s important to recognize that the build phase doesn’t mark a radical change in the types of workouts you do but rather a gradual addition of top end efforts and workouts. You should still be doing endurance/aerobic efforts and workouts during this phase to maintain the base you’ve already built. Long Saturday group rides coupled with a sweet spot or threshold workout during the week are sufficient for this purpose.

The first build cycle should focus primarily on VO2 max. In addition to a long group ride and a sweet spot/threshold workout two VO2 workouts should be done: one very short, perhaps even 30min with 3min efforts, and another longer workout of an hour with longer 5 and/or 8 min efforts. It’s important to have plenty of recovery between efforts. 2-3min is a minimum but depending on the effort level and number of intervals the recovery time can be up to 8-10minutes between intervals. If you’re crunched for time or your sustainable TSS doesn’t allow a heavy workload try adding some VO2 intervals to the end of a sweet spot/threshold workout by replacing a 12-20min interval with 2-3 shorter VO2 intervals.

You want to continue to do anaerobic efforts at the end of your longer intervals during sweet spot/threshold workouts and should do one 30min anaerobic workout each week. Do this workout on the trainer or find a short steep climb that will last 1-2min at anaerobic effort before a long Saturday ride. It’s important to do this workout first so as to be fresh and able to push out the required power levels.

The Second Build Cycle

In the second cycle begin incorporating harder efforts into your long group rides: take longer pulls, attack hills, and go for town sign sprints. Find a group that will push you hard if you want but allow you to sit in when needed. The second build cycle should begin to include race efforts. If you have a local race series start doing these once a week. Short criterium races are ideal even if you primarily race road. Your hard weekend group rides will develop the endurance you need for road races while the short crit races will help develop top end power and fatigue resistance. If you don’t have a local race series, develop workouts that incorporate intervals that simulate race scenarios. Simulate attacks and chases. Start by attacking hard out of the saddle for 30 seconds, settle into a VO2 max effort for 2 minutes and then settle further into a threshold effort for another 3 minutes. At the end of the 3 minutes sprint hard for the last 10 seconds. This workout will simulate the final moments of a race when top end power and fatigue resistance is critical.

The Build For Triathletes

Since triathletes require steady state threshold efforts, the build period should focus primarily on VO2 max and TT efforts. The first Build cycle should be predominately VO2 max efforts with one TT effort mixed with a long group ride. Short course triathletes should focus on hard VO2 efforts followed by short brick workouts. This will help with fatigue resistance and develop muscle tolerance for the all-important transition to the run leg. The second build cycle should incorporate two TT over/under efforts. Long course triathletes should be doing 40-60minute TT efforts while short course triathletes should be doing 20-30minute efforts. During these TT efforts you should gradually increase your power over a 30s-1min period to your VO2 max effort and then drop it back down to your TT effort taking the same amount of time. Ride for 2-5minutes at your TT pace and then ramp up the effort again. (TT pace should be whatever effort you plan to ride at during your race events not necessarily your threshold effort).

What About Sprinting?

It requires very little to achieve top end sprint performance and max sprint power can only be maintained for a short period. Use easy recovery rides to do 2-3 all out sprint efforts with 3-5minutes of easy riding in between. Sprinting at local crits or for town signs and short sprints in recovery efforts are enough to begin developing sprint power. Wait until the peak/taper phase to really start training sprint power. This should be the last two weeks roughly before your big A-race. 5-6 sprint efforts with 3-5 minutes of recovery done 2-3 times a week is about all you need to maximize sprint power for your big event. If you’re part of a team, use this time to perfect your lead-out train.

Racing During the Build Phase

Athletes often wonder how much racing they should do during the Build phase. This is largely determined by how much racing is available in your area and how much work you’re willing to do in those races. Some riders prefer to race into shape by racing as much as they can during the build phase in order to develop top end power. If you’re the kind of rider that uses small races to train, which means you’re not so concerned about winning as you are about working hard and putting in hard efforts, then you should back off on some of your harder efforts during the week. If you are trying to win and you predominately sit in and conserve energy during races, you should do your hard efforts throughout the week during your scheduled workouts. There is no reason not to race during this phase of training. Some athletes even begin racing during the end of the base phase. Try not to load a series of hard races at the start of the build phase and not race towards the end of the phase. Racing generally forces you to work harder than you normally push yourself training on your own. If you race hard in the first cycle and don’t race at all in the second you may not see improvement over the second phase.

If you have questions about the build phase or need help developing a training plan email Coach Dempsey at

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Human Power Performance