An athlete’s aerobic capacity can be evaluated and improved upon via the implementation of maximal aerobic speed (MAS) training. MAS is a measurement of an athletes running velocity at the point their VO2 max was reached (vV02 max), or their maximal oxygen intake. More precisely, an athletes MAS is the lowest running velocity at which maximum oxygen intake occurred, as the athlete may be able to continue to run faster beyond this point before reaching their anaerobic threshold (Berthoin et al, 1992). An athletes MAS score can be quantified by having an athlete complete a MAS test, providing coaches with a 100% MAS score that is specific to that individual athlete. Once an athlete’s 100% MAS has been established, intervals can be programmed that are pre-set to a percentage of an athletes vVO2max or MAS. This includes sub-maximal (e.g. 80% MAS), maximal (100% MAS) and supra-maximal (120% MAS) maximal aerobic speed based intervals, which when periodised correctly, may lead to an improvement within an athlete’s aerobic capacity.

MAS Testing

An athletes MAS can be established in many ways, including incremental shuttle based running tests (e.g. Yo Yo IR1, Multistage shuttle test, Montreal Beep test, etc.) and linear continuous running tests set to a specific set distance (e.g. 1200m, 1500m, 2000m, etc.) or a specific time trial (e.g. 5-min, 6-min, 7-min, etc.). When implementing a shuttle based test, the demands of repeatedly decelerating, changing direction and re-accelerating places a greater demand on the aerobic bioenergetic system. The repeated recovery requirements between each intermittent high intensity effort places significant demands on the phosphocreatine system and therefore, an athlete’s ability to resynthesise phosphocreatine stores. A muscles oxidative capacity plays a key role within phosphocreatine resynthesis, as the process of replenishing muscle phosphocreatine stores is heavily oxygen dependent.

When implementing a shuttle based MAS test, the athletes MAS is established by recording the final running speed achieved within the last running shuttle before the athlete ceases to continue with the test. The final running speed established when using shuttle based tests will be recorded in km/hr, and will therefore need to be converted to m/s to allow MAS training distances to be easily calculated (Baker & Heaney). Therefore, when implementing shuttle based MAS testing coaches need to be aware that an athletes MAS score will most likely be lower when compared to a linear based MAS test result. This inaccuracy requires the athletes shuttle based MAS score to be corrected using the following equation (Berthoin et al, 1992):

(MAS=1.34*MSST final speed – 2.86)

Berthon et al (1997) previously demonstrated a significant relationship between an athletes MAS established via a 5 minute time trial and MAS established via an incremental treadmill test to exhaustion within a lab. Research by Chamoux et al (1996) previously demonstrated that a 5 minute time trial was the most suitable running duration when establishing an athletes MAS score. These findings demonstrate the validity of implementing a 5 minute continuous running time trial to establish an athletes MAS within intermittent high intensity based sports. When implementing a time trial or set distance MAS test, the athletes actual MAS score is simply calculated by dividing the distance covered (in metres) by the time taken to complete the test (in seconds).

MAS Training

The desired MAS percentages can then be calculated from the athletes MAS score and implemented within a program based on the desired intensity of that particular session (e.g. sub-maximal session at 80% MAS, maximal session at 100% MAS, supra-maximal session at 120% MAS). The percentage of the athletes MAS is then multiplied by the duration of the programmed interval (e.g. 15 seconds running at 100% MAS) before being marked out as the required distance to be covered per 15 second effort (e.g. 100% MAS = 4.2 m/s = 63m per 15 second run). This would then be repeated for a set number of efforts (e.g. 15 s work : 15 s rest @ 100% MAS x 8) with either an active recovery (for lower intensity MAS training) or complete rest (for higher intensity MAS training) between each interval. This block of work would then be repeated for a set number of sets.      

Dupont et al (2004) previously reported significant improvements in aerobic capacity and 40m sprint performance post 120% MAS training intervention in soccer players. These findings demonstrate the simultaneous aerobic and anaerobic benefits of supra maximal MAS training in team sport athletes and other sports that demand both aerobic and anaerobic capacity. It is clear that MAS training offers coaches with an effective means of evaluating and improving an athlete’s aerobic capacity, which in turn will benefit aerobic performance within intermittent sports, therefore providing practitioners with effective form of metabolic conditioning that can be included within the overall performance program. To easily calculate and set programs based on your MAS score, please visit the ‘MAS Calculator’ within the resources section.  

Multiple sports are intermittent in nature, requiring athletes to perform repeated high intensity efforts throughout the duration of the event (e.g. team sports, racquet sports, combat sports, etc.). Russell et al (2016) previously investigated the movement demands of premiership soccer players and reported that players covered a mean total distance of 9.5km, a mean high intensity distance of 487 m, and a total of 656 accelerations per 90 minute game. Spencer et al (2004) reported similar findings within competitive field hockey, with the mean number of repeat sprints performed being 4±1 sprints per high intensity bout. The authors also reported that 95% of the recovery phase during each repeated sprint was of an active nature. It is therefore evident that a major portion of the total distance covered per game is done so at a low intensity, with athletes being required to manoeuvre to a more advantageous attacking or defending position whilst recovering between each high intensity effort. Such active recovery based movement places large bioenergetic demands on an athlete’s aerobic capabilities, therefore requiring athletes to possess a sufficient aerobic capacity. 

Aerobic Adaptations that Favour Anaerobic Performance

Bogdanis et al (1996) previously demonstrated that aerobic metabolism significantly contributes to repeated sprint performance beyond the first performed sprint. The authors reported that aerobic metabolism demands increased from 31% to 50% beyond the first sprint effort when performing repeated 30 second maximal sprints. Hoff (2005) previously reported a reduction in the distance covered and the amount of repeated sprint completed during the second half of competitive games, suggesting a depletion in glycogen scores may contribute to such a reduction in performance. The authors further concluded that an improvement in an athlete’s aerobic capacity would lead to an improvement in stored fat utilisation, therefore reserving stored glycogen stores for more high intensity efforts. These findings demonstrate the need for aerobic capacity performance in athletes that require repeat high intensity effort capabilities, therefore enhancing high intensity aerobic metabolism contributions, recovery performance and glycogen reservation.

High-Intensity Interval Training

High-intensity interval training involves repeated high intensity efforts set to pre-determined work to rest ratios over specific durations, allowing athletes to accumulate a greater amount of time spent training at higher intensities. Another key benefit of high intensity interval training is that the repeated work to rest format allows an athletes aerobic and anaerobic capacity to trained simultaneously. Tabata et al (1996) previously demonstrated that high intensity intervals performed at reduced recovery periods and all out maximal activity concurrently improved aerobic capacity (VO2max) and anaerobic capacity performance measures. Helgerud et al (2001) previously reported significant improvements in aerobic capacity (VO2max), lactate threshold and running economy in elite junior soccer players post high intensity interval training intervention. Such simultaneous aerobic and anaerobic performance improvements would be beneficial for any sport that requires repeated high intensity efforts (e.g. team, racquet, combat and endurance based sports).  

These findings demonstrate the benefits of improving an athlete’s aerobic performance within intermittent high intensity effort sports, and how such favourable adaptations can be developed via the correct programming of high intensity interval training. Another effective form of metabolic conditioning based training is maximal aerobic speed (MAS) intervals, which is explored within the second part of this article series (see ‘Increasing Aerobic Performance Part II : Maximal Aerobic Speed Training’).   

Plyometric training has shown to be an effective power-based training method within sports performance, with previous research investigations demonstrating significant improvements in vertical jump performance (Markovic et al, 2007), ballistic push-off performance (Potdevin et al, 2011), sprint performance (Rimmer et al, 2000) and change of direction performance when applied within a frontal plane of motion (e.g. lateral bounds) (Miller et al, 2006).          

Plyometric training derives from a form of jump-based training firstly formulated by Yuri Verkhoshanky as a means of increasing rate of force development in Soviet track and field athletes and was one of many pioneering training methods derived from Soviet research on athletic development. Verkhoshansky applied a particular form of plyometric training known as accentuated eccentric training, whereby the eccentric portion of a landing is ‘accentuated’ by having the athlete perform a prior landing from a greater height, therefore increasing the eccentric forces upon landing. The greater eccentric forces resulted in a greater magnitude of kinetic energy, therefore resulting in a greater transfer of energy during the ground contact phase and a greater rebound or take-off action.

Plyometric Mechanical Models 

Plyometric exercises can be performed in a variety of ways depending upon the desired training outcome and demands of the sport action being replicated. In particular, it is imperative that the kinetic demands of the sport are matched and not just the kinematics. This translates to the replication of ground contact times (kinematics), RFD magnitudes and power output (kinetics) seen within sports performance, which vary depending the sporting action. The three plyometric mechanical models that can be applied to replicate these varying sport demands are as follows:

Concentric Dominant

By definition a plyometric exercise involves an amortisation phase or ‘prior landing accentuated eccentric’ as previously described. However, many sporting actions require an explosive type ballistic push off without any form of prior accentuated eccentric contraction or landing phase such as a block start in sprint swimming or sprint events, scrumming within Rugby, takedowns within mixed martial arts, etc. Therefore, if an athletes chosen sport requires such explosive ballistic push-off demands, then the implementation of concentric dominant plyometrics is necessary. Furthermore, when taking an athlete through long term plyometric progressions, it is essential that an athlete can firstly land correctly and perform concentric dominant type jumps (in conjunction with strength training) before progressing onto more advance plyometric training forms.    

Tendon Compliance

Tendon compliance based plyometrics involve a prior accentuated eccentric (prior landing) and therefore an amortisation phase. However, upon landing the athlete flexes at the ankles, knees and hips to the degree that they feel necessary before exploding into the next secondary jump. This manifests itself as a ‘absorbing the depth’ type movement pattern when landing before jumping the next jumping action. This allows the musculotendinous unit to lengthen whilst storing kinetic energy, before recoiling and transferring this stored energy into the next planned immediate jump. This ability to store and utilise kinetic energy is vital to many sporting actions and is a key stage within plyometric progressions.       

Tendon Stiffness

Tendon stiffness is the ability to produce rapid RFD within the shortest ground contact time possible, and therefore involves little flexion at the ankles, knees and hips upon landing. As little change in joint angle occurs during the execution of tendon stiffness based plyometrics, most of the mechanical work occurs within the tendon rather than the muscle itself. For example, upon landing from a drop jump plyometric, the muscles that plantar flex the ankle perform a quasi-eccentric-isometric contraction. This means the muscles are being held isometrically within the same position before being eccentrically lengthened under load and can therefore operate at the high-force section of the force-velocity curve whilst the tendon undergoes a rapid stretch-recoil action. The greater the tendon stiffness, the greater the RFD and energy economy of the movement, as less actual muscle work occurs compared to a concentric dominant or tendon compliance-based jump.  

The mechanical differences highlighted between each of the following plyometric models demonstrates the need for coaches to fully understand the biomechanical demands of an athletes chosen sport before implementing plyometric training. Practitioners should also be aware of an athletes current plyometric training status, and where within the plyometric progressive model an athlete is at, before programming plyometric-based training within sports performance.    

The ability to be able to produce high peak ground reaction force is vital within sports performance. However, the high velocities involved within most sport actions requires athletes to not only produce high peak forces, but rather produce high forces within a short time frame. This athletic quality is referred to as ‘rate of force development’ (RFD) and is a direct extension of power production. RFD can be defined as the ability to produce force within a limited time frame (Gamble, 2009) or mathematically defined as: 

RFD = ∆F/∆t 

Where RFD represents an athlete’s rate of force development, ∆F represents the change in force from the initiation of the concentric action to the peak force achieved during the concentric action, and ∆t represents the change in time from the same corresponding force measures. This can be measured as the overall change in force from the overall time taken to complete the concentric action, or as the change in force between each individual time step during the concentric action (e.g. every two milliseconds). The latter being referred to as instantaneous RFD.

Olympic weightlifting methods require the ability to produce high power and RFD outputs, as heavy external loads are lifted in an explosive manner. Olympic lifts also involve a rapid triple extension at the ankle, knee and hip during the explosive 2nd pull phase, and therefore closely match the kinematics of sporting actions that involve the same movement demands (e.g. jumping, sprinting, etc.).

Baker (1996) previously reported a positive correlation between vertical jump, 20m sprint, loaded squat jump and hang power clean performance in semi-professional league players, suggesting that the athletes with higher hang power clean scores performed better at each of the other performance measures. A further study by Baker and Nance (1999) demonstrated a similar relationship between Olympic weightlifting performance and 10m and 40m sprint performance. These findings demonstrate the benefits of Olympic weightlifting within athletic preparation, providing a means of increasing power and RFD output in athletes. Such improvements power in RFD will ultimately (all else being equal) enhance the performance of the explosive-based movements often seen within sports (sprinting, jumping, striking, etc.).  

The classic competition lift variations are as follows: the snatch, and the clean and jerk. However, each Olympic lift has a variety of derivatives which can be applied to improve a certain key point when performing one of the main competition lifts (e.g. hang clean/snatch, power clean/snatch). Both the competition lifts and lift derivatives are of great use to the strength and conditioning coach. However, it must be noted that learning the Olympic lifts takes time and commitment from both the coach and athletes’ perspective, as the execution of the lifts is complex and therefore takes a lot of practice and correct guidance

This can be achieved by firstly introducing athletes to the Olympic lifts with technique bars and wooden dowels within warm ups prior to any strength and power-based gym session, which when accumulated over a season, adds to a high amount of good quality practice. During this time the strength and conditioning coach can look to other alternative training methods that increase RFD and power production in athletes, such as loaded jumps and/or plyometrics.

Another key consideration when programming the Olympic lifts within athletic performance is the load selected. Strength and conditioning coaches need to consider the purpose of why they are programming the Olympic lifts, which is ultimately, to increase power production that directly transfers to sports performance. Therefore, coaches need to select loads where peak power occurs when performing an Olympic lift variation. For example, a previous investigation by Kawamori et al (2005) previously demonstrated that the highest peak power and average power occurs between 50 to 90 %1RM when performing the hang power clean, and should therefore be programmed within that range when implemented within athletic preparation.   

It is clear that Olympic weightlifting training methods offer a high transfer of training effects to sports performance, as they match both the kinetic (RFD) and kinematic (triple extension, landing mechanics, braking mechanics) of athletic performance, and are therefore of great use to the strength and conditioning coach.

Olympic weightlifting and its derivatives (hang, power and pull versions) are often implemented within strength and conditioning practice as a means of increasing power production in athletes. However, the correct execution of such lifts requires practice and a good level of knowledge on behalf of the strength and conditioning coach. Therefore, practitioners may look to other approaches for improving power and RFD in athletes as a separate (and equally as effective) means of speed strength training, or whilst the athlete develops Olympic weightlifting competency.

The use of hexagonal bar jumps and loaded squat jumps as a form of speed strength training has recently been highlighted within research literature (Weakley et al 2018). Hexagonal bar jumps are performed with a hexagonal deadlift bar, and involve performing an explosive vertical jump whilst holding the hexagonal bar implement. Likewise, loaded squat jumps require the athlete to perform a jump with a loaded bar, but positioned across the shoulders as when performing a traditional back squat exercise.    

A recent study by Oranchuk et al (2019) demonstrated that vertical jump, RFD and isometric force performance improved in equal amounts after the completion of a high hang clean pull and hexagonal bar jump training intervention. These findings suggest that the use of loaded jumps as a means of increasing RFD within athletes is warranted and can be applied as an equally effective alternative to the Olympic lifts. However, in conjunction with the law of training variation (that being the need to apply different training stressors within athletes to force training adaptations), it is apparent that both loaded jumps and Olympic lifts could be used together within strength and conditioning programs.

Care must be taken when selecting loaded jump training loads, as peak power output has been shown to occur at varying weights relative to ones 1RM depending on an athletes training status and level of strength. Research by Turner et al (2012) demonstrated that peak power occurred when performing hexagonal bar jumps at loads ranging between 10-20% of ones 1RM back squat. Similarly, Stone et al (2000) reported peak power outputs at 10% 1RM back squat when performing loaded squat jumps, whereas Baker et al (2001) reported maximum power output values when performing loaded squat jumps between 55-59% of 1RM back squat performance. Therefore, strength and conditioning coaches should use loads ranging between 10-60% of back squat 1RM performance when programming loaded jumps with athletes whilst ensuring the exercise is performed at maximal speed in an explosive manner, and not at a restricted pace due to excessive loads.

The relatively simple execution of a hexagonal bar jump or a loaded squat jump, when compared to that of an Olympic lift, make the use of loaded jump training appealing within strength and conditioning practice. However, athletes must first demonstrate correct landing mechanics and possess adequate strength levels before embarking on a loaded jump-based program. Despite these pre-requisites, it is evident that loaded jump training is an effective means of improving power performance within athletes, and should therefore be considered within athletic preparation.   

Newtonian mechanics demonstrates that the greater the magnitude of ground reaction force generated, or the higher the amount of force that is applied to an object, the quicker the object or body will accelerate (dependent on the mass of the object / body that the force is applied to). Likewise, the greater the amount of torque generated by a muscle, the higher the level of joint angular acceleration. It is therefore evident that the ability to produce high magnitudes of ground reaction force and joint torques within sports is of great importance within sports performance.

However, what also must be considered is the limited time frame in which force and torque can be applied within sports. During locomotion (running, sprinting, changing direction, etc.) or when striking an object or an opponent, an athlete must apply rapid forces within a very limited time duration. Such limited time frames in which to apply force requires the athlete to produce equally rapid muscle shortening velocities, therefore equating to high power outputs in conjunction with: P = F x V

Where P is the power output, F is force generated by the concentric muscular contraction and V is the muscle shortening velocity. Power is defined as the amount of work completed within one unit of time (measured in Watts) and has been identified as a key performance quality within multiple sports.  

The ability to generate optimal power output within a short time frame has previously been linked to adaptations within the musculotendinous unit referred to as tendon stiffness. Tendon stiffness is the ability to quickly utilise kinetic energy during the amortisation phase when landing or when in locomotion (the eccentric to concentric conversion between landing and take-off). Chelly and Denis (2001) previously reported that leg stiffness (when calculated from hopping) was significantly correlated with maximal velocity sprint performance. Likewise, Kukolj et al (1999) previously reported a significant correlation between counter movement vertical jump performance (a test of explosive power) and sprint performance. It is evident that power output is a key performance quality within maximal sprint performance, both in the form of explosive power (e.g. jumping) and via musculotendon stiffness (e.g. locomotion).

Aragón-Vargas and Gross (2019) recently identified power output as a key indicator of vertical jump performance. Similarly, Kamandulis et al (2018) previously identified peak power is a key performance variable in boxing punch performance. It is evident that the ability to produce maximal power is of great importance to vertical jump performance, maximal sprint performance and striking performance, and should therefore be a key focus when preparing athletes that are required to perform such fundamental sporting actions. 

However, the ability to produce large power outputs is not only related to explosive based activities, but also to endurance-based sports. Endurance based athletes are required to produce mechanical work per foot contact, pedal stroke, swim stroke, etc. throughout the duration of a competitive event or training session. This ‘repeated power production’ quality is referred to as power endurance. Research by Spurrs et al (2003) investigated the effects of plyometric training on running performance, musculotendon stiffness and various performance measures. The authors reported significant improvements within the athletes 3 km performance, running economy, vertical jump performance and five bound distance tests. These findings clearly demonstrate the link between an improvement in running performance and running economy due to an increase in power production via musculotendon stiffness adaptations. It is therefore evident that the ability to produce high power output is of great importance across many sports, and should therefore be a key focus within athlete preparation.