Why Sweet Spot?

By Jason Schisler, Director of Coaching
 

A common thread in many of our early-season workouts is Sweet Spot training. There are many benefits to this type of work, but the primary reason we include it is because it offers most of the benefits of threshold training while allowing for faster recovery over threshold work. Despite this, it seems many athletes find these workouts quite challenging, so this article will lay out what Sweet Spot is, what it does and how to get the most benefit from this type of training.

 

First, what is Sweet Spot all about? Training zones don’t have firm start and stop points; the top end of one range overlaps the bottom of the next. While the goal often may be to train in the middle of a target range, Sweet Spot is a bit different. You want to target the transition point between tempo and threshold. Different training models will express this differently, one says Sweet Spot happens at 83-97%, another recommends 88-92%. This variation is likely part of the confusion. Looking at these numbers, the average athlete can span a pretty large power range, 30-35 watts.

 

Rather than worrying about these ranges, I like to define Sweet Spot as 90%. It is right in the middle of both of these ranges and fits well between the most accepted ranges used for tempo and threshold. It’s also much easier to remember one number in training, rather than the upper and lower ranges of a zone. In addition to that, Sweet Spot is about feeling. The effort should be hard, but noticeably easier than doing threshold work.

 

Now that you understand what Sweet Spot is all about, why should you bother? As mentioned above, you get the benefits of threshold training with less of the stress. These benefits include increased plasma volume, mitochondrial enzymes, glycogen storage and cardiac stroke volume among others. In training terms, the lower intensity allows you to accumulate more training load because you can complete a higher volume of threshold intervals or return to this type of training more frequently.

 

A pretty standard threshold workout is 2x20 minutes at 95-100% of FTP. This workout may be all most athletes can handle in a day, and it may take a few days before they feel ready for harder training again. But if they instead took the Sweet Spot approach to training and did 2x20 minutes at 90%, perhaps they would finish these efforts with enough reserve energy for a third interval or could add an additional intensity ride to weekly routines. Even though the reduction in power from traditional threshold training is relatively small, this change makes the sustainable duration for Sweet Spot effort much higher.

 

So why is it so hard? Bear in mind that while Sweet Spot training is less intense than threshold work, it is by no means easy. However, I believe a few factors lead to athletes experiencing Sweet Spot work as harder than they should. The first and most important one is the reference point (Functional Threshold Power or FTP) is incorrect. As most commonly defined, FTP is the maximum effort you can sustain for approximately an hour. We customarily evaluate FTP with the 20-minute test, subtracting 5% from the average power to adjust to this hour-long effort. The training we’re talking about here then should be 10% less than the power that is already 5% less than you have done for 20 minutes. Many athletes who have been training for a while become resistant to updating FTP reference points, even though fitness changes over the course of the season as training habits change (volume increases decreases, group rides come and go, taking more time off, etc.). If they’re trying to use an old reference point that is representative of a higher level of fitness they no longer have, athletes are going to experience training that is intended to be more manageable as more challenging. In essence, they’re doing Sweet Spot training at threshold power.

 

The other reason that athletes find these workouts hard is simply because they ride too hard. Even if the FTP reference point is current and correct, the mentality of many athletes is that more is better. Why would you do less than you possibly could? As pointed out above: because you can complete a higher volume of Sweet Spot work and recover from it faster. Rather than pushing at the limit, hold back just a little bit to reap the benefits of this type of training.

 

While our definitions above are built around structured Sweet Spot training, it need not always be so formal. Simply going out and riding hard for 1-2 hours will often have athletes spending a significant amount of time riding at Sweet Spot. Similarly, group rides, motorpacing and long, steady climbs often end up as Sweet Spot efforts.

 

Who can benefit from this type of work? Everyone, although Sweet Spot may fit in differently for different athletes at key points in the training year. Some examples include:

  • Early-season training: nearly everyone will benefit from Sweet Spot work early in the season when volume may be relatively low and the goal is to rebuild training load. The relatively high intensity and volume of Sweet Spot training leads to high TSS and can be useful in growing CTL. It also serves as an important precursor to higher intensity threshold work.
  • Time-trialists can use Sweet Spot training along with harder threshold work to build muscular endurance to sustain power for full 40k time trial.
  • Sprint- and Olympic-distance triathletes can take the same approach, while 70.3 or IM triathletes may use Sweet Spot a bit earlier before races to boost sustainable speed at race pace.
  • Criterium- and road-racers may want to return to some Sweet Spot work mid-season after a block of races with short, high intensity efforts to rebuild aerobic fitness.
  • Century- and Gran Fondo-riders, particularly those training for events with long climbs, can boost aerobic endurance and create muscular endurance for sustained uphill grinds.

As you can see, there is something for everyone when it comes to Sweet Spot training. Its benefits are wide-ranging. But it’s important to take a “hard, but not too hard” approach to squeeze the most juice from your lemon. Add some well-balanced Sweet Spot training to your routine and your fitness and race performances will thank you for it this season.