Many are interested in the best approach to scaling a session and scale based on time-available and their individual development as an athlete. 

Let’s look at the reasons you may adjust a workout relative to time or intensity.

1. Time-starved:  You review the prescription and simply don’t have time to get the session in with the time you have available, or you need to adjust distance (typically in the swim) to hit the session as expected.
2. Fatigue:  You have a tough session for the day, but your body is just not cooperating, so pulling back is the pragmatic decision for the day.

We are going to focus on the first part, but before we go on I cannot help but highlight something.  Pulling out of a planned hard interval session due to deep fatigue (your body just simply doesn’t have it) is not a sign of weakness or failure.  It is a critical and bold training management decision to enable consistency and effective training. Just this morning, I asked Purple Patch Pro Chelsea Sodaro to stop doing intervals and convert to a light day.  Is she a failure? She is not at all. She has done so much good work in the preceding weeks that the body now needs to absorb the prior training load, and this last session would only risk deeper fatigue, maladaptation, or injury.  Smart short-term honest decisions make great long term athletes.

With this little caveat, let’s transition to the main topic on hand — scaling around time.  Let’s begin with a breakdown of how we prescribe training— with a couple of key points to help you frame the mindset:

• We prescribe by time (duration) not distance in bike, run, and open water.  This is so that we can manage expected physiological stress and help training management across athletes.  Asking two people to run 13 miles can be a vastly different experience, from a Purple Patch pro taking 85 minutes, to some amateurs taking multiple hours. This is further impacted by terrain and environment.  It doesn’t make any sense for any athlete to measure training load by distance in bike or run.
• We prescribe pool swims by distance:  We are in a controlled environment — with fixed stop / turn points and it would be madness to prescribe most swim sessions on time.  You would be treading water for most of your interval rests!

These different instances impact your approach to scaling.  

Swimming: Let’s take the swim session as an example — and use our SF Squad to help guide you.  While we prescribe in distance (intervals of 25, 50, 75, 100 yards or meters, etc) in pool swims, we still think in terms of managing relatively equal stress.  Because swims are broken into intervals, each interval is going to take a different level of swimmer a different time. We will want to adjust many interval lengths, based on swimming ability.  To crystallize for you — in our 6 lane pool in San Francisco — let’s imagine I prescribe:

8 x 200 to 300 with 45-second rest.

The obvious question is what distance should each swimmer do?! The way this would work for San Francisco based swimmers would be:

Lane 1 (who can hold 100 yard repeats on a 1:10 send off — in other words, the pros):  Would do the full 300.

We then scale the distance for all other lanes.  Something like this:

Lane 2:  (1:20 / 100 yards):  275

Lane 3:  (1:30 / 100 yards):  250

Lane 4:  (1:40 / 100 yards):  225

Lane 5:  (1:40-1.50 / 100 yards):  225

Lane 6:  (2:00+ / 100 yards):  200

All swimmers intervals will take roughly the same time. The pros might take 3.5 to 3.75 minutes to swim their 300, Lane 6 might take 3.5 to 4.25 minutes to swim their 200.  No one is losing out by doing less.

This is how we prescribe scaled swimming according to level, BUT, now we need to scale to reduce the time any session takes.   The shift here is that scaling is occurring as an adjustment of your swimming against your prescription, instead of scaling your swimming versus faster swimmers.  In this case, we shift a little. Let’s continue to use our example of 8 x 300 (or 275, 250, 225 etc…).  If you are time-starved you would not further scale distance. Instead, you would typically scale the number of intervals.  So, instead of shifting 8 x 300 to 8 x 150 for the fast swimmers, I would shift 8 x 300 to 5 or 6 x 300. Maintaining the distance stimulus and limited the number of intervals.

The same can be said when scaling / reducing training time in the below examples.  Remember, you are looking in the mirror when scaling for time, not comparing to faster athletes:

Running:  8 x 5 min strong effort with 2 min rest.  Here, we would not shift to 8 x 3 min, instead we would scale to 5 or 6 x 5 minutes.  

Riding:  Let’s mix it up.  Imagine I prescribe a trainer session with a main set:

Two Rounds of:

8 min strong at 65 rpm

6 min very strong at 75 rpm

4 min hard at 85 rpm.

If time is against us, it is likely better to shift to a single round, instead of hacking away at the duration of each interval.

Of course, there are more nuances that come into play, but this is the general theme.   One final piece that might be helpful for you is the retention of the primary purpose of the session.  This is central to why I am so keen on athletes looking at the prescription and aiming to understand the mission.  

If you happen to be time-starved or have a need to shorten a workout, there is a specific way we recommend you go about it to any set:

1. Trim the Additional Set: The first thing to shorten or drop would be to trim the Additional Set at the end of the workout.  
2. Scale the Warm Up: Next would be shortening the Warm Up and/or the Pre-Main set.  Don’t cut them altogether and ideally, you would complete enough of each to ensure you are ready to go for the Main Set.  
3. Adjust the Main Set: If you still need to carve out more time, then cut back on the number of intervals and not the length of the interval. 

If you have additional questions regarding how to best approach your training, book a consult with a coach.