Physiology, Podcast, Training

Intensity, volume, rest, nutrition, coaching and triathlon myth-busting with Dr. Philip Skiba | EP#173

 March 18, 2019

By  Mikael Eriksson

​Intensity, volume, rest, nutrition, coaching and triathlon myth-busting with Dr. Philip Skiba | EP#173

TTS173 - Intensity, volume, rest, nutrition, coaching and triathlon myth-busting with Dr. Philip Skiba

Dr. Philip Skiba, one of the most sought-after coaches and consultants in the triathlon and endurance sports industry joins us to discuss the fundamentals of designing a training program. He also gives his viewpoint on a number of topics and busts some hard lived myths. 

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:

  • The physiological fundamentals behind effective training.
  • The volume vs. intensity debate.
  • How to include intensity in your training program. 
  • How to think about the rest in your training program.
  • Periodisation (or lack thereof).
  • Nutrition, and not falling for fad diets and the flavour of the month. 
  • Some common triathlon myths or misconceptions busted and explained. 

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About Dr Philip Skiba

0:56  -

  • Dr Skiba was an integral part of the team tasked by Nike to prepare Eliud Kipchoge and the other runners involved in the Breaking2 project.
  • He has also worked with the British Triathlon Federation to prepare the Brits for the London Olympics in 2012. 

Dr Skiba's background

6:10 -

  • I was primarily interest in cellular molecular biology in college, and completed a Masters in this subject. 
  • I then decided to go to medical school, and while there I became interested in exercise physiology - primarily because I was a terrible athlete! 

    I started learning more about physiology to find ways it could help me. 
  • The things I was working out turned out to be helpful for athletes that were good. 
  • I began training some professional triathletes who started doing well - e.g. winning World Championships.
  • I then had the opportunity to develop some of the training systems used by British Triathlon on the way to the 2012 Olympic, where they did very well. 
  • After that, it became one thing after another! I got hired to work on Nike's Breaking2 project, and since then have been working with them. 

Tools Philip used with professional triathletes

7:40 -

  • There are mathematical models that allow you to predict how athletes might perform, and understand how training stress comes and goes and how they respond to it.
  • Working with these tools, I could see athlete succeeding in spite of their training, and not because of their training.
  • A lot of athletes were doing far too much training.
  • An early example is Joanna Zeiger who was an Olympian. However, when I analysed her I realised there was far too much volume and not nearly enough intensity. 

    Once we applied changes to training (i.e. decrease volume and increase intensity) she went on to win almost every race she entered. At the World Championships for half Ironman distance she set a world record. 

    This showed the benefit in my methods! 
  • I wrote some of these methods into a software package which was use by British Triathlon in the run up to the 2012 Olympics. 
  • For a while I sold the programme, called Race Day Apollo, but it later became too much to train athletes as well as manage a publicly available software package. 

    I decided to support the organisations using it, and not continue doing it publicly. 

Physiological variables aiming to improve with training

10:36 - 

  • The three main variables are VO2max, threshold/critical power and economy (how much oxygen does it cost you to do what you're trying to do). 
  • Your VO2max sets the ceiling - it's your physiological capacity in terms of exercise. 
  • Critical power, and to some extent lactate threshold, determine how close you can approach that final limit, and how long you can maintain something close to that limit. 

    Economy plays an important part here too.
  • If you look at Mike Joiner's 1991 paper, you can calculate how some people will do at the marathon distance is you know their lactate threshold, their economy and their VO2max. 
  • We learnt through doing Breaking2 that we needed a certain combination of factors to make someone physiologically capable of running a two hour marathon. 

    But you can trade off - if someone has a slightly better economy you can cope with a slightly lower VO2max for example. 

    Nobody is going to be perfect, nor is it possible to train just one of those factors - you automatically train them collectively. 

    This is why it's a mistake to focus on any one thing, all of these factors are important. 
  • A good training programme will include things that improve all of these factors. 

    For example, running hard intervals above the critical power. 2 minute intervals on a couple of minutes rest repeated a few times over. 

    This works on VO2max, but you will find that economy and critical power also rise if athletes do this repeatedly.
  • We do 10-20 minute intervals when working on critical power.
  • All of these things necessarily improve each other.
  • The event you are hoping to do should be what guides the training programme, not necessarily the physiological system you're focusing on. 

Differing training programmes based on event

14:27 - 

  • Comparing different events: e.g. National team Olympic mixed relay, and a half ironman, there will necessarily be a difference in volume between the programmes. 
  • When you're working on Ironman you're thinking much longer rides - 100mile rides, with periods at the race pace you hope to maintain, or slightly faster. 
  • When you're doing something shorter, you just don't need that much volume. 

    Some volume is important to train the fatigue response of your muscles, but not as much as Ironman. 

    It's really important for shorter races doing to be a significant volume at race speed. 

    There are also tactical considerations in shorter races, e,g, pack riding. 
  • They require very different skill sets which the programme should focus on - the most important organ after all is the brain. 
  • Doing a lot of high volume training with lower intensity, provided you have athletes that respond to that, may result in a fair amount of success. 

    I personally would have a hard time training at athlete with a lot of volume, then throwing them into a race where they spend a lot of time at or near critical power. 

Physiological background for self-coached athletes

17:42 - 

  • An important thing to remember is that 'running form' is not the same as economy. 

    Athletes often try and find a coach to help with their form because they think it will make them more economical. 
  • We know that the body self-optimises. 

    One of my colleagues Isabel Moore found through her PhD that if you take complete novice runners and make them run for 6-weeks, their economy improves - without any coaching on their form. 
  • When you use things like motion analysis software or stop action photography, you find that the determinants of someones running economy in the mechanical sense are difficult to identify.

    Even once you identify them, it's difficult to know how you're going to get the person to change them. 

    For example, a difference of just a degree of two in the tibia when the bone strikes the ground is important. 
  • I don't think a lot of those things are visible by the eye. 
  • The best thing is probably just to run a lot. 

Plyometrics & strength training to improve economy

19:48 - 

  • There's very good evidence that plyometrics and explosive strength training can improve exercise economy.
  • It depends on who you're dealing with:

    E.g. A relatively new triathlete could do some basic plyometrics (box jumps, hurdle hops etc) and this could be very beneficial. 
  • A good book for this area is Running: Biomechanics and Exercise Physiology in Practice by Bosch & Klomp. It summarises a lot of this exercise, and goes from the very easy to the very difficult. 
  • All the professional athletes I deal with are on a good plyometrics programme. 

    The question then becomes, as they are truly advanced, are we getting any more out of the plyometrics. I genuinely don't know the answer to that. 
  • The science is the same irrespective of the sport. 

    If you understand the physiology, and the way to address this, the determinants are self-evident. 
  • For my work, it's about the coach, the athlete and myself all willing to be accountable. 

    You measure performance consistently and either the athlete is better or not better. If they're not, you need to change something. 

Improving athletes plateau 

23:53 - 

  • The volume versus intensity debate is always a good one.
  • One of the big dangers in sport is when you have a coach who was a former elite athlete, and they think what worked for them is going to work for everyone. 

    This is simply not the case.
  • I have often found athlete being asked to bend to the coaches programme, rather than the coach saying what is going to work for this particular athlete. 
  • Joanna Zeiger was a great example of that. We were very public with the things we changed with respect to her training. 

    She really had no intensity at all, it was just miles and miles. 
  • The first thing I do with any athlete or coach that brings me in on a consulting basis is look at the training, not just in terms of weeks and months but over years. 

    I ask what they have been doing, and what has been the change in performance. 
  • When you have someone who has plateau'd, and you're training them the same way and getting the same result, this situation is ripe for intervention. 
  • You can give them a stimulus they've not met before, measure performance and see what the result is. 

Volume vs intensity in elite athletes 

25:51 - 

  • There do seem to be volume responders and intensity responders, and almost everybody requires some element of both. 
  • It's not necessarily that I'll reduce the training hours spent, but what I might do is take an hour and change it into something else.
  • Volume is one of the main drivers of resistance, which is paramount to any endurance enterprize. 
  • Swimming and track cycling are good examples, completely huge volumes in training for very short competitive races. 
  • However in swimming it's been shown that once you get above 25-30,000 yards, you may not be seeing improvements in performance anymore. 

    I have high school students who come to my medical practice and are over-trained or injured, and they have been swimming 5,000 yards a day on a regular basis. 

    These are things where a scientist can intervene and offer perspective. 

Frequency of sessions

27:50 - 

  • Frequency is good in terms of reducing injury risk.

    Rather than stacking everything into one workout you cut it up into multiple workouts. 
  • There is probably also some benefit to training in a depleted state. 
  • Practice does not make perfect, perfect practice makes perfect. 
  • Particularly with a runner, when they start to fatigue and are not holding their form, then you may need to reduce the one session volume and break it into a couple of sessions. 

    You need to be sure you can maintain form or you run the risk of getting hurt. 
  • Looking at a large scale programme, there's interplay between frequency and volume. 

    Initially I may focus less on volume and more on frequency (e.g. 4 shorter runs, rather than 3 longer runs). 

    We may then start to build the volume - build the length of the runs, then come back to 3 runs for a short period, build the length, then go back to 4 or 5.
  • When you think about periodisation, the athlete should always be doing everything e.g. some intensity, some volume, some threshold work etc.

    The balance between them depends on where in the training cycle they are. You should be going from general training to specific training as you get closer to the goal event. 
  • At no point are my athletes doing no intensity and just volume. They always have a track workout, and during long runs there is always quality work for example. 

Intensity of sessions

30:57 - 

  • For the average triathlete every week they will have some kind of interval workout. 

    I don't believe in the 'micro interval' phenomenon. Short intervals feel easier because they are easier. 

    If you look at VO2 while people do intervals, it can remain low if you keep the intervals short. 
  • Usually, for example in a running programme, you may spend time running 200's, but in general long intervals are 400-800.

    You want something that will get you above 1.5-2 minutes to really drive VO2. 
  • If we're doing a volume period this interval workout may just be 4x400 during another run one day a week. 
  • They also have at least some element of threshold work, doing intervals of at least 5 minutes in length, if we're during a period of time where threshold isn't a focus. 

    Closer to a race they may be doing several 10 minute intervals, close to critical power or critical speed. 
  • I will try and skew the athlete in the way they respond - i.e. if they're an intensity responder, increase this aspect where possible. 
  • In general, I try to prescribe one interval workout and one threshold workout in each discipline per week.
  • When dealing with a person who is time limited, I typically become more polarised in my approach. 

    I'll typically give them tempo paced intervals within their longer ride - e.g. 3 or 4 x 10-20 minutes at 10% below critical power, during a 3 hour ride. 

    You're getting some intensity in there but it's not at the expense of a long workout. 
  • On another day I might give them a track workout, but again they'll do a reasonable amount of running both before and after the track part. 
  • A workout doesn't necessarily have to be just one thing, you can add quality into something that's longer, and get significant benefits that way. 
  • You need to be checking in with the athlete everyday and see how they're feeling. 
  • One of the best things about tracking training stress over time is that you can compare the objective stress with the subjective feeling of the athlete. 

    Where those two things diverge, it's time to intervene as the coach. 

    E.g. if the athlete goes to the track and they are still meeting their paces, but it feels a lot harder than normal, then it's time to reel it in.

    If they get past that point you reach the point of performance incompetence - i.e. they feel terrible AND they can't hit their paces. This is not a great position.
  • The advice I give to my age group athletes is that you should finish these workouts and still have a little left in you if you really had to do more. 
  • You can look at your athlete splits, and when you see them steadily declining you know the workout is not going the way you want it to go.

    Power analysis helps too, if you see the power dropping over the course of a 10 minute interval you know that they're either too fatigued or the power is too much for them at this point. 
  • This is what the analytical tools are helpful for - what is the athlete really capable of, not just what they tell you they are capable of. 

Planning in rest 

38:09 - 

  • If I have an athlete (and this happens in a lot of athletes) who I don't think will be completely honest with me about their level of fatigue, I will programme rest days and rest weeks very strictly. 
  • You don't get better from training, you get better in recovery from training, so rest is an absolute requirement. 
  • It won't usually be an entire rest week, but an easier week on a semi regular basis. 
  • If someone is starting to plateau, we might take a rest day or two before they start to decline, and then start harder work once they return.
  • When you're dealing with someone at the elite level who you are in contact with on a daily basis, you can then be more holistic about how you plan it.

    A microcycle might be 5-10 days. You're constantly looking at their data and seeing how they're responding, and can take rest days if they seem to start struggling. 

    It might not be an absolute rest day - maybe a 20 minute jog and then go have something for lunch. 
  • A key part of coaching is what I call the 'Jedi mind trick':

    Some athletes really don't like resting so you might need to make an athlete think they're not resting, when actually what they're doing is so easy it's not producing any stress at all. 
  • In the general case, I do rest as rest. 
  • Coaching is 99% communication! Most athletes, especially the amateur level, get better with almost any training you throw at them. 

    The main thing is talking to the person and finding out when they're not feeling good/feeling sore/things aren't going right. 

    If you stop it them and control the problem then, you could stop an injury that's going to put them out of action for weeks. 

Tracking improvement


  • Short time trial efforts on a semi-regular basis can be beneficial. 
  • There are lots of ways of doing it - you could ask someone to do it at the same RPE and see if they're getting faster for example. 
  • One of the favourites we do with elite marathon runners is a progressive long run. 

    Starting out extremely easy (8:30/mile), and by the end their perceived exertion is close to race exertion. 

    You can look at the progression and the pace they end up at, which can be a good performance measure in and of itself. 
  • What I learnt from Breaking2 was really understanding the interplay between what is easy and what is hard, and listening to the athletes subjective feeling. 

    These guys were literally the fastest people alive, and they were able to identify when they needed some time off. This is a mindset that is unfortunately very rare in elite sport. 
  • Social media has been a real curse, because everyone is talking constantly about their training. 

Nutrition & fuelling for training

41:41 - 

  • In general, the problem I see is people eating too little, and/or not eating the right things. 
  • Over the last 10 years there has been a big interest in low card and ketogenic diets, which are just not appropriate for high performance. 
  • If you read people like Louise Burke, it's very clear that these kinds of diets do not improve endurance performance. 
  • You need to be on a high carb diet - this doesn't mean eating whatever you want. 

    Athletes should eat to hunger and should come to a stable weight. It's not about being as light as you can, it's about coming to a reasonable weight where you can perform at your best. 
  • Particularly in endurance sports, we do have a problem with energy deficits. 
  • For the average triathlete it's probably not worth the trouble to train in a fasted state. 

    At a higher level it may be important to manipulate some of those dietary things - e.g. going out for a long run when you've not had breakfast. 
  • It's difficult to know the performance benefits of these things, and I err on the side of making sure people are well fed.

    You're just not going to train well if you don't have enough calories on board. I'd rather have my athlete 5 pounds heavier and healthy. 
  • I recently helped an old friend who is a runner, and after years she found she had bad bone health in her early 40's. 
  • Almost none of us are in a position where we're going to win an Olympic medal, we do sport because we enjoy it. 

    This needs to be the focus. Chasing the last 1% of performance is almost never worth the sacrifice.

Myths and misconceptions

49:47 - 

  • One of the most important things I talk to people about is supplements, and why they're not helpful.

    Ron Lawn, a physiologist, used to say 'if it works, it's probably illegal, and if it's legal, it probably doesn't work'.

    This is very true, we know there are a very limited number of things that benefit athletic performance. 
  • We know that high carbohydrate works, to an extent dietary nitrate works, and caffeine works. There's not much beyond that that's legal or safe!
  • Some people are endlessly taking vitamins and supplements but we know that they don't work. A lot of times when things do work it's because they are contaminated with something else. 
  • Over the years I've seen many high school athletes who have been referred to me by a primary care physician with funny liver function tests. 

    Thats one of the signs someone might be on oral steroids. They usually swear up and down they're not doing anything illegal, but when I've had their supplements tested they've actually been contaminated with anabolic agents. 

    Very often a lot of these come from factories in China and they only work because they're contaminated with something illegal. 
  • You need to think about the potential results for the rest of your life - what does it potentially do for your job and your reputation. 
  • As discussed above, I don't think the ketogenic diet is beneficial for endurance performance. 
  • When you look at weight loss, you find that diets that are calorie limited with result in weight loss provided you stick to the diet - there is no magic diet but they just need to restrict calories. 

    We do have good evidence that diets high in saturated fats are not good for you, as they accelerate heart and cardiovascular diseases. 
  • The example I use is 'open your mouth and look in the mirror, you have the teeth of an omnivore' - you have molars that grind grains, incisors that cut meat. Evolution is telling us that we are meant to eat everything! 

    I think we do ourselves a disservice when we try and outsmart millions of years of evolution. 
  • Eat a balanced diet, don't eat too much, eat enough green things and do some exercise and you're going to be okay.
  • The other major myth is that people think they can execute the training plan of some great athlete and then they will also be great. 

    For example, when working on Breaking2 Eliud Kipchoge published some of his workouts. I immediately had athletes talking to me about trying to execute his workouts.
  • His workout of the year when I showed up in Kenya at his track was 16x1200m at 4:30/mile pace. That would kill the average athlete! 
  • Great athletes are genetically superior to the rest of us. They have certain innate gifts that make them great at what they do. 

    Even if Eluid has never ran, he would still run faster than 99.99% of people on the planet because it is how he is built. 
  • There is no magic, no easy way and no secret. You need to find what works for you and execute that. 

Key takeaways

  • Finding what works for you as an individual is super important. 

    There are people that respond well to high intensity or volume and vice versa. This is something you need to figure out for yourself. 
  • 99% of coaching is communication - it's such an important factor and it's a two-way street. 
  • To incorporate intensity, you can start with 1 session of short intervals (1.5-4 minutes) and one second session per discipline of longer intervals (5-20 minutes).
  • Regarding diet, keep things healthy and simple. Don't be restricted in terms of calories and macronutrients. Don't fall for fads - both with diet and supplements. 

Links, resources and contact

Links and resources mentioned

    Connect with Dr Philip Skiba

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    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.

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  • great podcast/topics.what metric do you use to find intensity responder vs endurance responder?

  • “In general, I try to prescribe one interval workout and one threshold workout in each discipline per week.”

    Sounds very intendity based. This is 6 workouts of intervals in a week!

    • It is. Goes to show that there is more than just one way to skin a cat. Note though that this is “in general” and Dr. Skiba mostly works with professional athletes who can handle more training load and recover better. I imagine that he might change this general approach when working with age-groupers with jobs and families and who can’t recover quite as quickly as the pros.

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