Why high-intensity training is better
It is probably fair to say that most swimmers and swim coaches see
the number of hours spent in the pool as the main ingredient of swimming
success and distances of 6 to 10 kilometres per day is common in elite swimming
circles. Is this the key to success, or is there an alternative approach
that can produce even better results? This article aims to stir up the debate
by suggesting the traditional high-volume model of training will not optimise
performance, especially for 100-metre and 200-metre swimmers.
It is written not from a swimming coach's perspective but in the
light of research on swim training, scientific analysis of the demands of
competitive swimming, and running training methods that have been shown to
optimise performance. Swimmers should read on with open minds and may then
choose to apply some of the principles to their training programs.
Research into the effects of high-volume swim training on
performance suggests there is no advantage to piling on the kilometres. The
legendary US physiologist Dave Costill has undertaken a great deal of research
on swim training over the last three decades. In one study, his team of
scientists followed two groups of swimmers over a 25-week training period. Both
groups began with once-daily training, but one group moved to twice daily
training in weeks 10 to 15, reverting to once daily for the rest of the study
period. At no stage of the 25-week training period, did this group show enhanced
performance or increased aerobic capacity as a result of their extra training?
It was a waste of time.
In another study, Costill tracked the performance of competitive
swimmers over four years, comparing a group averaging 10 kilometres per
day with a group averaging 5 kilometres per day to changes in
competitive performance time over 100, 200, 500 and 1600 yards. Improvements in
swim times were identical for both groups at around 0.8% per year for all
events. Again, even though one group did twice as much training, both groups
benefited to the same extent in the long term.
To quote Costill directly: 'Most competitive swimming events last
less than two minutes. How can training for 3 to 4 hours per day at speeds that
are markedly slower than competitive pace prepares the swimmer for the maximal
efforts of competition?' Research from France supports Costill's conclusions. A
team of scientists analysed the training and performance of competitive 100-metre and 200-metre swimmers over 44 weeks. Their findings were as
- Most swimmers completed two training sessions per day
- Swimmers trained at five specific intensities. These were swim
speeds equivalent to 2, 4, 6 and a high 10 mmol/L blood lactate concentration
pace and, finally, maximal sprint swimming
- Over the whole season, the swimmers who made the most significant improvements were those who performed more of their training at higher paces.
The volume of training did not influence swim performance.
Feeling comfortable is not the point
The only conclusion to be drawn from this research is that faster
and no longer training is the key to swimming success. Nevertheless, the
high-volume, low-intensity training model probably remains the most common
practice among elite swimmers, with even sprint swimmers focusing on clocking
up the kilometres rather than more race pace- specific training.
One of the reasons for this high-volume bias is that swimmers and
coaches believe that swim technique, efficiency through the water and the
'feel' of the stroke are optimised by spending many hours in the pool. I have
heard swimmers say they do not feel as comfortable in the water and confident
about their technique unless they complete high doses of training. As a
non-swimmer, I am happy to admit my ignorance and to concede that the technical
aspect of swim training is essential. However, the idea that high-volume
training equates to superior race technique has no logical basis. If you told a
100-metre runner that the best way to optimise his sprint technique at maximum
speed would be to complete many miles a week at 10 kilometres pace, you would be
laughed off the track! Track sprinters focus on workouts and technical drills
carried out at high-intensity and positively avoid low-intensity/high volume
training in the belief that it inhibits power development.
The same must be true of swimming to a large extent; if a swimmer
wants to increase stroke efficiency and technique during a competition, surely
the best way to do this is to train at a target race pace. The more training time
is spent at the target race pace, the more comfortable it will feel in competition.
Dave Costill says: '...large training volume prepares the athlete to tolerate a
high volume of training but likely does little to benefit actual performance'.
When swimmers talk of feeling comfortable in the water, they may be referring
to the sub-maximal speeds they perform in training, not the maximal efforts
required in competition.
Not only does high-volume training offer no benefit for swim
performance, but it may also have negative effects. Two known consequences of
high-volume training are depletion of glycogen muscle stores and fatigue of the
fast-twitch muscle fibres, both of which will reduce the effectiveness of
high-intensity race pace training sessions and severely compromise any
Research has also shown that periods of high-volume training
reduce the force production in the fast-twitch muscle fibres, which are
essential for producing the fastest swim speeds. It has been shown that sprint
swimmers have quite high proportions of fast-twitch muscles - over 60% in the
deltoid and quadriceps. High-volume training does nothing for these fibres:
indeed, it will dampen their force production by reducing the shortening
velocity of the muscle contraction. In this way, high volume training can
change fast-twitch fibres into the slow-twitch variety.
This probably explains why 'tapering' is so effective at improving
performance for swimmers, as the fast-twitch fibres can recover during
the period of low-volume training. It is known that maximal power increases
after a tapering period, probably due to the fast-twitch fibres reproducing
their high-velocity contraction properties. The French researchers mentioned
above analysed the effects of tapering on swim performance and found that
swimmers who used the most severe tapers - reductions of about half normal
training volume - produced the biggest performance improvements.
This begs the following questions:
- If such dramatic tapers in training are required to optimise
performance, why are training volumes so high in the first place?
- Would it not be better for swimmers to develop power positively during the training period?
Examination of the demands of sprint swimming events will help to
answer these questions.
The metabolic demands of swimming
The shorter the swim event the greater the demand on the
anaerobic energy systems. This is particularly true of the 50 metres, 100
metres and 200 metres events, lasting from around 20 to 120 seconds. The longer
events, from 800 metres upwards, demand a larger contribution from the aerobic
energy system. Evidence for this comes from blood lactate concentrations
following 100 metres and 200 metres competition swims, which are a very high 16
to 20 mmol/L, suggesting that a great deal of energy is derived from the
anaerobic breakdown of glycogen, resulting in lactic acid as a by-product. The
highly anaerobic nature of sprint swim events would support the argument for
more high-intensity and less high-volume training.
Some athletes and coaches go wrong by assuming it is best to do
training that will reduce blood lactate concentrations. This philosophy is
based on the idea that high lactate is bad and will harm
performance. This leads to training programs that focus on 'lactate
threshold' training to improve the turnover of lactate and enhance the ability
of the aerobic systems to produce more of the energy required for the event.
There are two problems with this model of training:
- You need to be careful about assuming high lactate levels are a
bad thing. Remember that lactic acid is the by-product of the anaerobic breakdown
of glycogen. Lactic acid splits into the H+ ion and the lactate ion. It is the
acidic H+ ion that is the bad guy, interfering with force production in the
muscles and reducing the rate of glycolysis, thus slowing the athlete down. The
lactate ion diffuses through the muscle and into the bloodstream, with
no evidence to suggest it has any negative impact on muscle function or energy
production. The lactate ion can be recycled in the energy production
cycle and used positively to help produce energy. Therefore, a high level of
lactate in the blood is not wrong in itself: it is merely an indicator that a lot
of anaerobic energy production is occurring. The training adaptation you are
seeking is not a reduction in lactate production, but rather an increase in the
buffering of the H+ ion. Training at high intensities and so generating high
levels of lactic acid helps the body get used to the increase in H+ in the
muscles and improve its ability to buffer the acid;
- Anaerobic glycolysis involves the fast breakdown of glycogen
into energy-giving phosphates, while aerobic glycolysis involves a much slower
breakdown. Without the anaerobic energy systems, maximal power and high speeds
would be impossible, as the muscles would not get a fast-enough supply of
energy. If you want high power, you have to have high levels of anaerobic
For sprint swimming, anaerobic capacity is a good guy, and it
needs to be developed. If an event places high demands on the anaerobic
system, the athlete needs to become more anaerobic! This may seem odd to those
of you with traditional beliefs about training, but it is true. By focusing on
high volume aerobic training to reduce lactate levels, you are
compromising your anaerobic fitness, which is the most important attribute for
competitive success in sprint swimming. For sprint swimmers, lactate threshold
training geared to keeping lactate levels low is, I would argue, irrelevant.
For swim distances up to and including 200 metres, the accumulation of high
levels of lactate does not matter: indeed, it is probably a good thing as it
reflects a good anaerobic capacity. For longer events, such as 800 metres and
1500 metres, where the aerobic system is much more important, lactate-threshold
training would be relevant, as swimmers need to maintain an intensity level for
much longer, relying on the aerobic energy system.
The race pace model of training
All the research mentioned above implies that
spending more training time at high-intensity levels, at and above race pace,
will offer greater benefits than swimming lots of kilometres per day at much
slower than race speeds.
In the world of running the focus of training is now on 'pace'
rather than lactate levels or heart rates. By using pace to monitor the
intensity of training, the athlete is switching into a performance mentality,
ensuring the training is specific to the competitive event.
Middle distance running coach Frank Horwill created a five-pace
system of training, which involves performing regular, quality training
sessions at two paces higher than race pace, race pace itself and two paces
slower than race pace. If you are a 1500 metres runner, you will complete
interval workouts at 400 metres, 800 metres, 1500 metres, 5000 metres and 10000
metres race paces. This model of training breeds a philosophy that values high-intensity ahead of high volume.
The coaches referred to above also recognise that different events
call for different kinds of training. The 5 kilometres running event - which
takes about 12 to 15 minutes - requires a high proportion of aerobic training
and 5 kilometres pace specific workouts, while the 800 metres event, lasting
about two minutes, requires a high proportion of anaerobic training and 800
metres pace workouts. I would argue that this kind of training model would
serve competitive swimmers much better than the traditional high volume
There is evidence that the difference between swimmers who reach
the Olympics and those who do not is due more to the distance achieved per
stroke than to stroke frequency. The way to increase your distance per stroke
is to increase the force generated by the active muscles and achieve an optimum
position in the water. This is best achieved by high-intensity training, to develop power in the water at a race pace.
How can swimmers change their training to enhance power at pace
speeds? Again, there may be lessons to learn from running. The 100 metres swim
takes about 50 seconds, and so is similar to the 400 metres track event; the
200 metres swim takes about 110 seconds and so is analogous to the 800 metres
running race. It may, therefore, be possible for swimmers to improve their
performances by modelling the training of middle distance and long sprint track
For example, an international 800 metres runner will carry out a
preparation period of aerobic capacity training with continuous running at 10
kilometres pace and slower, plus interval training at a 5-kilometre pace. The 200
metres swimmer's equivalent could be the usual high-volume training programme.
This base training phase will be followed by more specific
training, with more 5-kilometre and 10-kilometre pace runs and some more
interval workouts for the anaerobic system, at 800 metres and 1500 metres pace,
probably about three times a week. The 200 metres swimmer's equivalent could be
to maintain a high volume but include more above lactate threshold pace
workouts and race pace or close-to-race pace interval workouts three times a
week: for example, 10 x 100 metres at 400 metres race pace, with 60 seconds
This phase is followed by a very intense pre-competition phase of
training, the goal of which is to maximise the athlete's anaerobic capacity.
Aerobic training is cut to a minimum maintenance level, and high-intensity
anaerobic sessions at 400 metres, 800 metres, and 1500 metres pace performed
about 5 to 6 times a week. For the swimmer, this could involve a morning swim
at an easy lactate threshold pace or below, with a very high-quality race pace
and faster than race pace interval workouts in the evening. For example, 8 x 50
metres at 200 metres race pace, with 60 seconds rest.
The competition phase for runners will maintain aerobic and
anaerobic fitness with maintenance training and plenty of recovery between
races. For the swimmer this could involve some 'aerobic' slow-speed workouts
and some race-pace and sprint workouts, probably limiting training to 5 to 6
times per week.
The best middle-distance runners probably perform a maximal sprint
workout once a week throughout the year to keep speed up to scratch. Swimmers
could also incorporate this into their programs with, for example, 10 x turn
into 20 metres max sprint with three minutes rest, once a week.
I have argued, based on research, analysis of the energy demands
of swimming races and the training methods of comparable athletes that swimmers should focus on high-intensity rather than high-volume training.
More specifically, swimmers would benefit from plenty of race pace training to
develop power and efficiency in the water at the speeds they use to compete.
The following feedback, in January 2016, on this approach to training was provided by Grant Bubb, a USA triathlete.
I am currently 33 (male). I ran cross-country and swam as a high school student. I kept running after high school, but stopped swimming, mainly due to too much time/volume in the pool as a kid. After not swimming for 15 years, I started swimming again about a year ago for a triathlon that I completed last summer. Rather than putting in the long-hours, high-volume, and swim-by-the-clock techniques that I was familiar with from my youth (similar to what you mentioned in your article), I instead adapted my run training plan to swimming.
I swam two or three times a week, usually one day as interval training (12 x 100m or 6 x 200m) or short distance (3 x 400m) and the other day as long-distance (1 x 2000m). Over time, I found that my 100m swim (1:20) and 400m run (1:18), 200m swim (2:48) and 800m run (2:42), and 400m swim (5:42) and 1-mile run (5:40) average training times are very similar to each other.
Long story short, after 15 years of not swimming and six months of training, swimming only 2 or 3 times a week, no more than 45 minutes at a time, I finished my first-ever 1.9 km open-water swim in about 32:30 (1:41 per 100m) last August. This is a little slower than I can run an equivalent distance of 7.6 km, but it was both open-water and the first leg of a half-Ironman distance triathlon, so I was going all out.
I took four months off swimming (Sep to Dec 2015), due to work requirements, and started up again about a month ago. Using the same "training program," I have got my 1500m pool time down to about 22 min.
While l am aware that this time won't get me to the Olympics any time soon, my limited experience over the past year supports your research and shows that low volume, high-intensity training can be both effective and time-efficient.
Although my years in the pool as a child (age 5 - 17, 5-days a week, year-round) certainly helped me develop my technique and might suggest that a non-swimmer may not experience the same success in my "training program" as I have this past year, I think it's a sound training program for someone who already has the basic technique but does not have 10-hours a week to dedicate solely to swimming.
I followed the typical advice for high-intensity interval training, e.g. a 1:1 work: rest interval. So, if my 200-meter work interval took 2:48, I then swam easy for 2:48 before beginning my next work interval. The rest interval usually ended up about half the distance of the work interval, as is the case with my run training.
The information on this page is adapted from Brandon (2002) with the kind permission of Electric Word plc.
- BRANDON, R. (2002) Why high-intensity training is a better model than high volume training for swimmers, especially sprinters. Peak Performance, 167, p. 8-11
If you quote information from this page in your work, then the reference for this page is:
- MACKENZIE, B. (2006) Why high-intensity training is better than
high-volume training [WWW] Available from: https://www.brianmac.co.uk/swimming/swimspeed.htm [Accessed