Cycling vs. Running ‘which burns more fat?’ and ‘which is harder?’

I’ve followed a thread on the Facebook and there some views aired on ‘which burns more fat’ and ‘which is harder’.

So which is it? Lets find out:

Muscular stress

Running is a high impact active, it involves repeatedly striking the ground with impact force of roughly 2 -3 times body weight. That means that as a 70 kg human being, your leg muscles, bones and ligaments are subject ~210 N of force every single step of the way. Now cycling, on the other hand has negligible impact. The bike is supporting your body weight and eccentric forces acting on the musculature and bones are negligible. It’s worth noting this is true of road cycling, but not mountain biking.

Muscle contraction type also differs. In cycling muscle contractions are concentric, that is the muscle is lengthening. This is also the type of contraction that produces the least force. In running there’s the whole array of muscle contraction type: concentric (in propulsive phases) and eccentric on the breaking phases. The degree of muscle activation in the running movement actually occurs just before ground contact in running as the body ‘pre-empts’ the impact.

So which is harder on the muscles? Running by far. This is the reason we see bike races lasting weeks, while just one marathon takes weeks to recover from. You can do a massive amount of cycling before needing to stop.

Why is it ‘easier’ to run hard than cycle hard? In cycling the volume of muscle used by the activity and requesting oxygen from the respiratory system is less (60% versus 80% in running).

Ventilatory and cardiovascular stress (heart + lungs)

In both sports, trained athletes are able to attain ‘VO2max’ -that is maximal aerobic capacity, or the maximum amount of oxygen that your body can absorb. The body, like a combustion engine needs oxygen to produce energy: fuel + oxygen ≅ energy; heat + work. VO2max represents a ceiling of how much energy can be ‘burned’ aerobically. Where VO2max can’t be attained it’s unlikely that that exercise will be as effective at burning fat as these ‘big muscle group’ exercises. Other factors leading to performance in sport are efficiency and energy derived through other (anaerobic) mechanisms, also at which point one reaches Lactate threshold (LT), which varies from sport to sport and basically defines rates of sustainable exercise.

For sub-maximal exercise, a roughly linear relationship  exists between heart rate and energy expenditure -regardless of exercise modality; the unit cost of oxygen per amount of energy remains very similar regardless of ‘metabolic substrate’ (that’s fuel; Carbs, Fat, Protein). So what we’re seeing is if you cycle at the same intensity you run, you’ll burn round about the same amount of energy!

Excess post-exercise oxygen consumption (EPOC) is also about the same when comparing cycling and running, so post exercise fat burning remains about the same for both.

So which is harder on ventilatory/cardiovascular system? They’re the same more or less, it depends how hard you exercise and not how you exercise.

So which burns more fat? We’re back to the question of exercise intensity, rather than modality…

N.b. one important aside: LT will likely come a different stages in the same person doing the two sports. Generally LT is higher while running than cycling, except trained cyclists: If you’re a runner, runner is ‘easier’. If you’re a cyclist, cycling is easier. If your neither, then running is easer. Non-cyclists find it hard to reach VO2max on a bicycle.

Mental stress

The much ignored nervous system: the one that actually gets you up, out and exercising is obviously also an important factor.

Both sports provoke a large amount of cognitive load to people new to them: There are literally billions of ‘factors’, degrees of freedom open that the mind has to deal with. Think about what’s going on: posture, muscle activation, sensory feedback from the body, sensory feedback from the environment, cognitive interference, spatial processing and navigation, etcetera… An awful lot more is happening that just sitting on the couch! This can cause an overload of the neural structures that have to process the information. Hence it is interpreted as ‘unpleasant’ by those unaccustomed to momentum sports. People beginning sport often make subconscious efforts to reduce cognitive load by exercising indoor, listening to music, exercising at a reduced intensity, picking exercise modalities which minimize the amount of, or disassociating themselves from the activity at hand by using distraction techniques, such as counting strides, singing, thinking about something else.

With practice a person develops automatic ‘coping mechanisms’ (schema) where things that would normally take up their attentional resources become automatic.

So which is ‘less stressful’ I am not aware of a comparison between exercise modality and rate of arousal (although it probably has been done), so have to go on common sense here. I would guess running causes a greater amount intrinsic stimuli while cycling causes a greater amount of stimuli from the environment. In colloquial: Running hurts more than biking, but the movement is slower, so you have less things like cars, obstacles, dogs and potholes to deal with, biking is more stressful due to environmental factors. Given rates of participation in sport I’d guess about the same as cycling and running have a very similar amount of participants.

Coming next we’ll get Ricardo to throw swimming into the equation.


Nilsson, J. and Thorstensson, A. (1989) ‘Ground reaction forces at different speeds of human walking and running.’ Scandinavian Physiological Society,  136(2) pp. 217-227.

Scott, C. B., Littlefield, N. D., Chason, J. D., Bunker, M. P., Asselin, E. M. (2006) ‘Differences in oxygen uptake but equivalent energy expenditure between a brief bout of cycling and running’ Nutrition and Metabolism, 3(1).

Keytel, L. R., Goedecke, J. H., Noakes, T. D., Hiiloskorpi. H., Laukkane, R., van der Merwe, L., Lambert, E. V. (2005) ‘Prediction of energy expenditure from heart rate monitoring during submaximal exercise.’ Sports Science, 23(3) pp. 289-97.

Ekkekakis, P. and Petruzello S. J. (1999) ‘Acute Aerobic Excercise and Affect.’ Sports Medicine, 28(5) pp. 337-347.

Wilson, M. (2008) ‘From processing efficiency to attentional control: a mechanistic account of the
anxiety performance relationship.’ International Review of Sport and Exercise Psychology, 1(2) pp. 184-201.

Derakshan, N. and Eysenck, M. W. (2009) ‘Anxiety, Processing Efficiency and Cognitive Performance. New Developments from Attentional Control Theory.’ European Psychologist, 14(2) pp. 168-176.

Sport England (2013) Active People Survey 7. [Online][Accessed on 14th November 2014]

Pre-season training for cycling and triathlon -2015 starts now!

pre-season training is usually the part most people over look, here’s why its good to get it right:

Okay, so I’m working backwards this year and will be ‘peaking’ in December… But for most people NOW is the start of the off-season. I’ll take a couple of weeks of over Christmas ;-).

pre-season training for cycling and triathlon makes part of larger ‘long term’ training cycles

It’s the ‘rest period’ in the ‘macro-cycle’ that is the season. The main benefits however are mental. If you’ve been at something for months on end, it’s good to it a break. A couple of weeks seems like an eternity not to train but in actual fact it’s just enough time to freshen up for the following year. Physically, there are also important considerations: including strengthening the body, replacing depleted nutrients and broader rest period to recover from 10-11 months of non-stop training. Note that far from being a period of no training (although a week or two is in most cases a good thing) this period is actually characterized by doing a number of different activities to bolster recovery, rest and rebuilding.

other sports activities are important:

Cycling (road cycling specifically) reduces bone and so activities that result in ‘osteogenesis’ -that’s bone development become important. These activities are those that involve weight bearing and ‘impact’ activities. So running, gym, field sport and mountain biking.

I’m not sure how acute the reduction in bone mineral density is in semi-serious or recreational cyclists, however it’s at least equivalent to sedentary people.

Other benefits come from training movements you’re not used to, for example field sports require power and changes of direction and a series of eccentric movements you simply don’t find in cycling. So ligaments and supporting structures are also strengthened through these activities.

So in a nutshell, it’s strength and bodily integrity with which to face the season that we are building.

Use the off season to build solid foundations in technical aspects of your sport. These technical aspects might include bike handling skills in cycling, or technique in swimming:

mountain biking:

Mountain biking can be a great way to develop bike handling skills, specifically ‘vision’ control and balance over the bike. Because the ‘relative speed’ (speed relative to your environment). Riding single track at 25 kph can feel like you’re flying along, however the speed is actually low and you’re not that likely to hurt yourself should you come a cropper. Mountain biking is good too, because there’s little or no cogitative interference in the acquisition of these skills: What this means is you just ‘do it’ rather than think at all about what your doing. The more you think about something, the more you distract your subconscious brain from the important things like getting out the way of that tree your cycling towards!

Mountain biking...

Mountain biking helped sort out my bike handling back in the day. Thanks to my team mates for encouraging me and teaching me!


Going to the pool a little bit de-trained will expose flaws and weaknesses in your technique, so it’s a good point to see whether you’re going wrong (video analysis and a good coach work great), then build it up. There’s an order of priority for building an effective swim stroke, essentially you work on position (balance, kick),  hand entry (important not to develop injury), catch (‘grabbing’ the water),  pull (pulling yourself through the water), rotation (rotating your shoulder to about 45º on the entry) and recovery… I’m no expert. But if you have any question on it, get in touch and I’ll put you in touch with Ricardo.

be patient with rest periods.

Endurance athlete have an absolute hatred of ‘staying still’ and rest: Just do it. It as important as training.

be patient with the cross training

Endurance athletes also have an absolute hatred of the gym and other forms of cross training and frankly I can’t blame them. If you’re used to the outdoor and the pleasure it is to run or cycle through the world, and the ‘fix’ that these sports provide, obviously being stuck in a room under artificial light with a bunch of meat heads eyeing each other up is going to be nothing short of miserable.

However, big improvements can be found by building up your strength in the gym and then maintaining your strength gains through the season with just a couple of weekly sessions. So rather than fear the weight gain, think of the greater (eventual) power at threshold and sub-maximal economy that a strength training phase will afford you.

In a nutshell

Final word

While there have been pioneering researchers who have found these alternative forms of training to be better than the ‘tried and tested’ methods, people are surprisingly slow making the switch. What I’d say is that neither rest, strength training or cross-training are anything but bad for you! What’s more, training is a gave of averages and ‘marginal gains’ so that while the benefits might not turn you into superman next season, they’ll certainly be there; there are no miracles, just hard work.

Mike Schultz on training peaks has a good piece on weight training: Don’t need much more than that although different coaches will coach this differently.


Arnstein, S., Øyvind, S., Marius, B., Morten, L., Jan, H. and Jan, H. (2010) ‘Maximal Strength Training Improves Cycling Economy in Competitive Cyclists’, Journal of Strength and Conditioning Research, 24(8) pp. 2157-2165.

Warner, S. E., Shaw, J. M. and Dalsky G. P. (2003) ‘Bone Mineral Density of Competitive Male Mountain and Road Cyclists’, Bone, 30(1) pp. 281-286.

Zupan, M. and Petosa, S. (1995) ‘Aerobic and Resistance Cross-Training for Peak Triathlon Performance’, Strength and Conditioning, 17(5) pp. 7-12.

your christmas cycling training or damage limitation!

don’t let Christmas cycling training get in the way of your Christmas (or vice versa!)

The problem with Christmas is the huge quantities of food consumed and time constraints on training and ‘pressure’ to over indulge. As a pro cyclist, my coach would always give us training on Christmas day because of this. It’s hard to ‘work’ in this periods, so think not of the quality of the training but think of it as damage limitation. I found 4-5 hours of specific training would be next to impossible to do with any gusto on Christmas day.

cycling christmasthink of training in the holidays as an escape, a damage limitation exercise!

As cyclist I used to love a short but solid training session on Christmas and I think it was due to this that I’d always be the strongest cyclist on the team right up till March. I’d be flying. It felt good to get out into the mountains, up into the cool air or rain and beautiful views. People don’t understand this, so there’s no point arguing, just get out and do. This way you can also enjoy the food, with worrying too much. Your form wont go backwards.

I’d suggest setting yourself a distance, say a 90km cycle or 16km run. And just doing it as quick as you can manage. This will account for most of the Christmas pudding you consume! You wont train anything in particular, but it’s the realist best we can do. Disturbed sleep, the food and whatever your training status mean following any training metrics becomes next to impossible.

In terms of food choices, Christmas is not the time to diet, however avoiding sweets and the snacks that are spread around. The turkey, ham and garnishing aren’t that bad diet wise.

after Christmas

After Christmas it’s important to get back into your normal training routine as quickly as possible. This is more important than avoiding any excesses over the period. Christmas breaks habits and routines and to train well you need a certain amount of structure and routine around, food, sleep and of course the training itself.

Happy Christmas!