ABSTRACT

Take yourself further with your preparation for the new training year with an additional strength program alongside your endurance training. Your ‘off-season’ is the most opportune time to harness a new level of fitness. With only a few races over your base training period it allows for you to utilize this time to build your strength without compromising your race fitness.  Increased muscle fibre recruitment, increased resistance to fatigue and a potential increase in speed endurance are only but some of the physical adaptions that you can expect from this training.

Strength training for cyclists has been a topic of debate over the years because of conflicting theories, which lead back to the argument of whether strength training was creating risk of negatively affecting a cyclist’s power-to-weight ratio due to gain in muscle mass. But is there really a negative effect at all??
When we look at a cyclist’s endurance performance we look at their ability to maintain a sustained power output over a given distance for a certain period of time. Strength training, when coupled with endurance training (Cycling), can contribute towards a cyclist’s endurance performance by improving exercise economy, delaying fatigue, improving anaerobic capacity as well as enhancing maximal speed (Ronnestad. B , Mujika. I. 2013).
There are two generalisations for strength training which look at low load/high repetition (>15repetitions per set) to potentially build muscle endurance and then there is the high load/low repetition (4-15repetitions per set) which looks more at hypertrophy, strength and power. According to research there is little or no additional benefit of explosive strength training (with the exception for sprint/track cyclists perhaps) or strength training that involves a low resistance/high repetition on improving endurance performance. There are however, numerous studies that show the effectiveness of concurrent heavy strength training (heavy load of 4-10 repetitions per set) and endurance training on endurance performance.
In a study by Aagaard and Anderson (2010) it is believed that there are a few adaptive mechanisms that may assist in not only long term endurance performance (30-180mins) but also in short term endurance performance (0-15mins).
The first adaptive mechanism looks at increased recruitment of Type IIA muscle fibres, also known as fast twitch-oxidative muscle fibres, which are used more during sustained power activities and are more resistant to fatigue. With a higher recruitment of these fibres, the muscles in which they are found are able to contract forcibly for a longer period of time before giving in to fatigue.
Secondly concurrent strength and endurance training increases maximal muscle strength as well as increasing the rates at which muscles can develop power to overcome a resistance. This increase in maximum strength and force development mean that a cyclist can create a pedal thrust force against a given wattage which will now seem relatively less difficult to overcome, and will in turn have a beneficial contribution to the enhancement of endurance performance.
With this form of concurrent strength and endurance training there has been little evidence of excessive muscle growth or increases in muscle mass caused from this training in comparison to usual responses to strength training. This may be due to a counteracting effect of endurance training. Endurance training can create an atrophy stimulus in the muscles leading to a reduction of muscle fibres. In another study by Aagaard et al. (2010) after a 16week concurrent strength and endurance training regime they took samples of muscle fibre from the quadriceps muscles from a group of male Elite cycling athletes which showed a significant increase in type IIa muscle fibres but at a sacrifice of type IIx (Glycolytic) muscle fibres. The sacrifice of Type IIx muscle fibers is not as detrimental as they are much more susceptible to fatigue and therefore should not affect the endurance capacity of the athlete. Other adaptions or mechanisms which could lead to the enhancement of endurance performance also include decreased oxygen uptake, decreased heart rate and decreased lactate levels during prolonged training (30-180mins)(Ronnestad et al. 2010).

Although heavy strength training is beneficial, cyclists are cautioned that initial response to strength training is a delayed onset of muscle soreness (DOMS) which may cause heavy/tired legs. During ‘Off-Season’, athletes do not have races to keep in mind and thus can use this time to get into a routine with ample recovery time for muscular adaptions.  It is advised that athletes use a low intensity start point for approximately two weeks in order for the muscles to adapt to training, focusing more on technique over this period.
In conclusion, there is evidence to support the addition of strength training to an endurance training program. The strength training programs should be approximately two sessions a week and should be structured to enhance the above mentioned adaptions and to complement the endurance program. Athletes should do exercises that involve similar muscle groups to those used in cycling and should perform between 2-4 sets of 4-10reps per set of each exercise.

References:
Aagaard P, Anderson JL. Effects of strength training on endurance capacity in top level endurance athletes. Scand J Med Sci Sports 2010: 20(2): 39-47.
Aagard P, Anderson JL, Bennekou M, Larrson B, Oleson J, Crameri R, Magnusson SP, Kjaer M. Effects of resistance training on endurance training capacity, muscle morphology and fibre type composition in young top-level cyclists. Scand J Med Sci Sports 2010
Hausswirth C, Argentin S, Bieuzen F, Le Meur Y, Couturier A, Brisswalter J. Endurance and strength training effects on physiological and muscular parameters during prolonged cycling. Journal of Electromyography and Kinesiology 2010: 20: 330-339.
Ronnestad BR, Hansen EA, Raastad T. Strength training improves 5min all out performance following 185mins of cycling. Scand J Med Sci Sports 2010
Ronnestad BR, Mujika I. Optimizing strength training for running and cycling endurance performance. Scand J Med Sci Sports 2013.
Wang L, Mascher H, Psilander N, Blomstrand E, Sahlin K. Resistance exercise enhances the molecular signalling of mitochondrial biogenesis induced by endurance exercise in human skeletal muscle. Journal of Applied Physiology 2011: 111: 1335-1344.