Podcast, Training

Base training: off-season do’s and dont’s with James Teagle and Lachlan Kerin | EP#201

 September 30, 2019

By  Mikael Eriksson

Base training: off-season do's and dont's with James Teagle and Lachlan Kerin | EP#201

Base training_ off-season do's and dont's with James Teagle and Lachlan Kerin

Scientific Triathlon coaches James Teagle, Lachlan Kerin and Mikael Eriksson get together to discuss base training for triathlon and endurance sports. What should you do (and what shouldn't you do) in your off-season.

Discuss this episode!

  • Let's discuss this episode and the topic in general. Post any comments or questions in the comments at the bottom of the shownotes. Join the discussion here!

In this Episode you'll learn about:

  • What is "base training" or the "off-season" - how long does it last, when does it start, when does it end, and what are the objectives of it?
  • Should you take time completely off training?
  • Methodologies for structuring your base training
  • Common mistakes to avoid in base training
  • Considerations other than training to make the most of your base training phase

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Definition of the off-season and base training

  • James' view
    • The off-season is when athletes take a break from training for about 1 to 2 weeks.
    • After that, I start a preparation phase for my athletes. They are mentally preparing for their next season and do some light intensity sessions.
    • After that, my athletes start with the base phase from around 8 weeks.
    • Then I start with the build phase which, for me, still counts as the off-season. The off-season is done as soon as the first race started.
  • Lachie's view
    • I use two phases: First, not doing any swim - bike - run training from 2 weeks up to a month; secondly the base phase where we start doing more general training that I use for the preparatory phase for a race.
  • Mikael’s view
    • I find a minimum of 2 weeks off necessary, if the training load during the year is higher the athlete make need more.
    • After that, I start with a 4-week period of light training which I call a transition period.
    • After that, the base phase or general preparation starts which can take up to 5 or 6 months.
    • In general, the off-season doesn’t mean doing nothing, but it’s the time to do other things. Swimming, biking and running are allowed but it should be without the purpose of training.
    • It is important to have a mental break.
    • You can go out doing other activities which don’t have to be hard.
    • A longer break can be important to give the body the recovery it needs, getting lost of niggles. Seeing a physio fits in this.
    • You shouldn’t worry too much about the loss of fitness.

Objectives of the base training phase

  • Building the aerobic capacity is the big objective.
  • There is a fair bit of stimulus with a majority of low steady efforts but the intensity should be kept in the training. The intensity can be gradually building up, for example starting with a long run and building up with some tempo in it.
  • In swimming the technical aspect is very important. Also in biking technical aspects as pedalling efficiency are important but there should also be a focus on position on the bike.
  • Strength work is used in all three sports. In swimming, we have pull work, low cadence on the bike and hills for the run.
  • Strength work in the gym is also implicated in this phase.
  • The big aim is being consistent week in week out. The volume gradually builds.
  • For the intensity, the different energy systems are trained which can be as small as doing strides or 8 x 1’ high intensity or integrating accelerations in a long ride. Doing a little bit of everything. 
  • General health like looking after your sleep is very important in this period. This is not the time to overtrain. 
  • You can put on some weight (ex. Christmas period), don’t focus too much on weight. After that, you can start to focus more on it. 

Methodologies used in base training

  • After a couple of weeks of training, it’s time to see where your fitness level is by testing. 
  • In the first few 8 weeks, the focus is on aerobic training and doing some consistent work. 
  • After that, we test again to see if general fitness improved. Testing will be done throughout that period to see if there is progression.
  • The main focus is aerobic before going to work on more specific fitness.
  • The training is, of course, dependent on what type of triathlon we’re training for. In the case of Ironman, this is a good period to do trail running for example. 
  • This is also the period to do some long easy swimming instead of intensity. Not every session has to be hard. 
  • It’s important to look to last year and assess your strengths and weaknesses. This period is a good opportunity to work on them.
  • In this period it’s important to look at family life, work etc. and adapt training to this.
  • Looking at what races are coming up but also looking back at last season and where the athlete is at this moment is the starting point. 
  • Strength training is used in this period.
  • In general, we work on everything but look at what will be the main focus in which phase of the general base period (for ex. Technique, VO2, maintenance work)
  • You need flexibility in the planning. 

How to know you are getting base training right?

  • This is certainly important for the self-coached athlete
  • The number one key: is the program achievable? Are you doing the number of sessions as prescribed? Are you consistent?
  • In terms of how you are feeling, sleep is important in this phase. Lack of sleep can catch up with you further in the season.
  • You shouldn’t compare everything to your personal bests. It’s about progression. You don’t want to be in peak form yet.
  • We can use testing to see where we are but we are not looking to be our best at this time of the year.
  • It’s important to stay motivated. We want to avoid chronic fatigue, acute fatigue is ok but not for every week.
  • When doing a training camp, you shouldn’t overdo it, no massive amounts of training.

Common mistakes to avoid in base training

  • Avoid lack of sleep.
  • Avoid energy deficiency.
  • Don’t forget the balance in life. It’s the time of year to give back a bit, not take.
  • Don’t over complicate things. It’s about getting the training done and enjoy the training.
  • Important to get enough food in. You need to avoid an energy deficit. 
  • You shouldn’t lose the sense of fun in training.
  • Don’t rush it!! Don’t get too fit too soon!!
  • Don’t forget the focus on strength
  • You need to plan your training. 

Considerations outside of training for the base training phase

  • Again, make sure you enjoy your training.
  • Go and get a bike fit.
  • Get a nutrition plan, are you eating right?
  • Using methods like meditation, mindfulness…
  • It’s a good time to get a blood test done as early on (transition phase).
  • See a physio to get rid of certain niggles.

Key takeaways

  • Use the transition phase to get things right. It’s important to have some good sleep. See a physio to get rid of certain niggles. It’s the time to be with family and friends.
  • As soon as the general preparation starts, don’t rush into things. You want to avoid being too fit too soon.
  • The most important thing is to make sure you love the training and enjoy every moment of it. Motivation keeps us going.

Links, resources and contact

Links and resources mentioned

Connect with James and Lachie

Connect with host Mikael Eriksson


Hi! I'm your host Mikael,

I am a full-time triathlon coach and an ambitious age-group triathlete. My goal is podium at the Finnish national championships within the next few years.

I first started the website Scientific Triathlon in autumn 2015 as a passion project to share my learnings with a larger triathlon audience. Later on, in early 2017 I started the podcast That Triathlon Show. 

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Let's discuss this episode and the topic in general. Post any comments or questions in the comments below. I'll be here to reply and take an active part in the conversation, so don't be shy! 

Mikael Eriksson

I am a full-time triathlon coach, founder of Scientific Triathlon, and host of the top-rated podcast That Triathlon Show. I am from Finland but live in Lisbon, Portugal.

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  • OK, so let’s try this section… James emphasised (and both of you agreed) that this is not a good time for personal bests, at least not in the northern hemisphere. But for many of us triathletes, apart from transition, prep or base it’s also running season. We want our 5k, 10k, half marathon or marathon PBs, and it seems easier to tackle them based on the fitness accumulated over the summer than it would be in the spring, especially out here in central&northern Europe, where snow and ice don’t melt until March. Can you reconcile the need for base training with your October/November running ambitions?

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