APRIL 19TH 2017



track and field runner

The dreaded “H” word. As exhausting and relentless as hills are, though, Hill Repeats are immensely valuable for runners. Lactid acid build-up can start fairly early on in a Hill Repeat workout depending on a hill's grade (incline or slope). When it sets it, your breathing will shorten. This is because your muscles need oxygen to function properly, and when you run up a hill, you make more muscles function than you would if the ground were flat. As a result, lactic acid starts to build up more quickly than usual. This is why hills are a fantastic way to prepare for better utilizing lactic acid and mitigating how much it slows you down. It also helps you lower body strength.

As an aside, I love the long run. I tend to do some pretty great thinking during these hours on the road. No matter what kind of runner you are, you should be incorporating a long run at least once every two weeks in your training, though once a week is a better option. It’s important to note here that one person’s long run isn’t necessarily the next person’s long run. During my first two years of undergrad at Rutgers, I my long run was 7 miles long. Currently, however, my long run is 17+ miles. It all depends on your fitness level and goals. 

On the topic of the Long Run-Fast Finish – the basic idea here is to incorporate your LT pace in your long run. For example, if your run is 10 miles long, you could run the first eight miles at your regular long run pace, and the last two miles at your marathon goal pace. Be sure to limit your marathon goal pace to a small portion of your run. Long Run-Fast Finishes are similar to Fartleks, because they both aim to simulate race conditions, and build your tolerance for lactic acid build-up.

track and field runner

Yes, the word “fart” is in there. Go ahead. Get your laughs out. Fartleks are probably my favorite on this list. “Fartlek” means “speed play” in Swedish and it really is just that: pure fun and play that can be completed anywhere: track, trail, road, or waterfront esplanade (gotta love Portland). They are an incredibly versatile run that can be either distance-based or time-based, and you set the marks!

I do these workouts a lot and you’ve probably heard of them before, but while they may be used interchangeably it should be noted that a tempo run is just a popular type of lactate threshold run; there are others.When your body gets to the point where shortness of breath starts to kick in and your muscles are getting heavier, you have likely reached your lactate threshold (LT). 

When you reach this point you are now running anaerobically, a state which is much more difficult to maintain. If you “go anaerobic" in the last mile of a 5k or even a 10k, this is okay, but when you’re trying to complete a training run or a longer-distance race, you don’t want to push beyond your threshold (anaerobically) for too long.

LT pace that is faster than your easy run pace, but slower than your 5k or 10k race pace. So, for example, if you’re 5k pace is 7:30 minutes a mile, your threshold pace can range from 7:45 minutes to 8:15 minutes per mile pace (depending on your fitness). The mileage or amount of time you run a threshold run really depends on your training and goals, but generally you should shoot for a minimum of 2-3 miles at threshold pace, more though if you are training for a time goal for a half-marathon or marathon. Threshold runs are a great way to gain aerobic fitness and are great runs for all race distances. A Tempo Run (TR) is a run that maintains your LT pace for a longer period of time, at least 20 minutes.





So, in no particular order, here they are:

When your body doesn't get a sufficient amount of oxygen to power your muscles, lactic acid starts to build up in an effort to do so. During faster paced workouts, you may have noticed that your breathing is more shallow, or that your muscles feel like they are on fire and have turned into cement blocks. While there is much more science that goes into it, these are all symptoms of lactic acid build-up. [1].

[1] Mind the Science Gap. "Burn Baby Burn: The Truth About Lactic Acid and Exercise," June 1, 2013.


Have you ever worked out to the point where you feel a slight burning sensation in your arms or legs? Well, that sensation results from an increase in lactic acid production.


Coach Wilfredo Benitez

Coach Wilfredo Benitez is a USATF Level I certified coach. He adopts a training philosophy that is holistic in nature. He believes that a person’s work situation, nutrition, sleep, hygiene, and ability to manage stress are all related to their training and running goals.

For a distance-based Fartlek workout on a track, you could run the turns on the track at a moderate pace and the straightaways at a harder effort. You could continue this pattern for [x] number of minutes or miles. You could also run your hard effort every other city block. You set the rules, and the possibilities are plenty. The key is to alternate between moderate efforts and fast efforts continuously. After some time, your body will "go anaerobic" during a harder effort, and begin to produce lactic acid. This means that you will start to feel tired and heavy. Because your hard efforts are followed by rest periods, you will be able to sustain this state of duress for longer than you would during a race. In a sense, therefore, the Fartlek workout simulates race conditions for your body, which has many benefits. One is that it helps to delay the point during your race at which lactic acid starts to build up. Another benefit is that Fartlek runs build mental toughness.

Here's an example of a potential Fartlek workout:

Hill Repeats, like various other types of runs we've covered so far, aim to simulate race conditions, and build your tolerance for lactic acid build-up. The added bonus of these workouts is that when you encounter hills in a race or new running route, you will have more leg strength, mental strength, and overall capacity to take them on. Remember that when running uphill, proper posture is important; avoid slouching. 

Now get on out there and get your Fartlek on, or show lactic acid who’s boss! Happy Running!

This blog post was originally posted, and adapted from Eat Run and Done.

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