– Written by Gergely Kis, Qatar
One of the biggest challenges for the athlete that suffers a long-term injury, such as ACL rupture, is to maintain the previous level of cardiovascular fitness and overall conditioning. Many athletes will lack either the time, the motivation, or the resources to supplement their rehabilitation sessions with attention to fitness training. Bridging the gap between the cardiovascular fitness and strength deficits and safely returning the athlete back to their sport is the focus of the physical coach at Aspetar.
When an athlete stops participating in high levels of physical activity because of an injury, the physiological changes that occur are usually referred to as detraining. Detraining is the partial or complete loss of training-induced adaptations, in response to an insufficient training stimulus. Detraining characteristics may be different depending on the athlete’s training age (their history of training) and the duration of their training cessation1.
Given that the injured athlete greatly reduces their physical activity levels, maintaining muscle mass whilst simultaneously avoiding gains in fat mass can be challenging. The magnitude of muscle loss during injury is an important concern for the athlete when considering the level and duration of rehabilitation required before returning to full functional capacity2. Two or three weeks of detraining have been shown to cause the following decrements in highly trained subjects: Muscle oxidative enzymes decreased by 13 to 24%, performance time decreased by about 2 to 5% and VO2max decreased by about 4%3. It is recommended to provide an exercise stimulus (especially resistance exercise) for the uninjured muscle groups (e.g., upper body) to prevent any unwanted reductions in regional lean mass that may subsequently affect whole body muscle mass and metabolic function8.
The factors underpinning the reduction in VO2max depend on the duration of training cessation. They are mainly central maximal cardiac output (Qmax) during the first 3-4 weeks, and mainly peripheral afterwards, which relate to adaptations at the muscles that improve their ability to take on and process the oxygen. Considering that central adaptation and maladaptation are not specific to the trained muscles, alternative training can be implemented to avoid or limit detraining while an athlete is injured. For example, one leg cycling represents an exercise modality that can be used to limit the central effect of training cessation in injured athletes. Olivier et al. (2010) randomized 24 soccer players with ACL reconstruction in a control group that followed a classic rehabilitation program and an experimental group that added aerobic training of the non-operated leg to the rehabilitation program. Stroke volume and VO2max were maintained in the experimental group while they decreased by ~20 and 10% respectively in the control group. Arm cranking represents an alternative modality of cardiovascular training that is commonly used in the conditioning of spinal cord injury patients5. As we know oxygen transport to working skeletal muscles is challenged during whole-body exercise. When an athlete is using his upper body only, for example during arm-cranking exercise, this elicits a maximal oxygen uptake (VO2max) corresponding to approximately 70% of the value reached during leg exercises. Considering that, arm cranking allows us to reach exercise intensities that should be high enough to maintain or limit the decrease of Qmax6.
A modified training program can avoid or reduce detraining. If an athlete can maintain a certain level of exercise, they can retain a greater percentage of their baseline fitness levels. The intensity and duration of this ‘level of exercise’ remains controversial, is specific to each sport and it will depend upon an athlete’s baseline fitness level. Modified training strategies have been shown to delay the onset of cardiorespiratory, metabolic, muscular, and hormonal detraining. Maintaining training intensity seems to be the key factor but training volume can be reduced by 60 to 90%, training frequency reductions should be no more than 20 to 30% in athletes7.
Regaining pre-injury levels of conditioning is essential for the athletes to optimize performance after returning to play. Similar to effective training programs, reconditioning programs also need to follow training principles. The time required to recover pre-injury neuromuscular and cardiorespiratory levels may highly vary among athletes based on several factors including: time of training stimuli cessation or reduction, amount of individual detraining-induced effects, individual fitness levels and sport-specific requirements9. Mindful of any post-surgical restrictions of weight-bearing status10 our current practice at Aspetar is to introduce physical conditioning sessions for the rest of the body in the early phase of rehabilitation and some cases even prior to surgery to prevent deconditioning effects. The goal is to maintain cardiovascular fitness and increase the functional capacity of the athletes through the application of resistance training that does not compromise or risk the injured area.
Typically, the athlete is referred to the physical coach by the physiotherapist 3-4 weeks post-surgery. During the first session an assessment is performed to establish post-surgery fitness status and determine the parameters for training prescription. Assessments are being performed throughout the rehabilitation process at 6-week intervals, at the beginning and the end of each microcycle. These tests not only provide us with constructive feedback on athlete improvement, but they are also helping to motivate and set realistic training goals for the athlete. The training program is linear periodized, divided into 4 micro cycles, and designed by following the FITT-VP principles (Frequency -Intensity-Time-Type-Volume-Progression).
Physical conditioning is one of the 4 crucial aspects that need to be considered for the RTS (Movement quality, Technical and Tactical retraining, and Training load)11. Problems that exist following ACL surgery cannot be solved by one professional but a coordinated effort among the surgeon, physiotherapist, physical coach, and sport rehabilitator is required for successful rehabilitation and return to play.
A successful fitness outcome relies also on the long-term commitment of the athlete to complying with and completing the training program. The physical coach has an important role in educating the athlete about what is expected of them and what they can expect throughout the rehabilitation period.
PHYSICAL ASSESSMENT TESTS
Upper Body Strength tests
The Concept2 Dyno is a dynamometer that is reliable to assess the strength of the athletes12 and is widely used by athletic clubs and the police force as well as by researchers for strength assessment13,14.
Initial Strength Assessment (5 rep test)
1. Seated Bench Press
2. Seated Row
Upper body endurance test
· 1 min Push Ups
Core Stability tests
1. Trunk flexor endurance test
2. Trunk lateral endurance test
3. Trunk extensor endurance test
4. Prone bridge test.
Cardiovascular fitness tests
An incremental submaximal test on the upper body ergometer or leg cycle ergometer is used for the cardiovascular endurance estimation of the injured athletes during their initial assessment. The incremental exercise test is determined by different variables the starting stage, the consecutive work rates, the increments, the duration of each increment and the athlete’s heart rate. These variables can be modified extensively to suit the purpose of the training program or the individual and have proved useful in identifying and monitoring individuals or team’s adaptation to training15.
Submaximal performance testing is a way of estimating either VO2 max or aerobic fitness in sports medicine. The test protocols do not reach the maximum of the respiratory and cardiovascular systems. Submaximal tests are used because maximal tests can be dangerous in individuals who are inactive for a period due to injury. Options include:
Upper body ergometer (UBE) increment test
Outcome measures:
· Total time (min)
· Effort level (power/watt)
· Heart Rate (bpm)
· Heart rate recovery (1min/2min)
· Rate of Perceived Exertion (RPE)
Wattbike Increment submaximal test
Outcome measures:
· Total time (min)
· Maximum mean power (MMP)
· Power to weight ratio (w/kg)
· VO2max estimate (ml/kg/min)
· Heart rate (bpm)
· Heart rate recovery (1min/2min)
· Rate of Perceived Exertion (RPE)
Yo-Yo Intermittent Recovery test 1
Testing objective:
· To assess aerobic capacity and recovery ability
· Outcome measures:
· Total time (min)
· Total Distance (m)
· Maximal Aerobic Speed (Km/h)
· Average Heart rate (bpm), Heart rate max (bpm), Heart rate recovery (bpm)
· Rate of Perceived Exertion (RPE).
(Table 2) is an example of a weekly development of on field running session we use, depending on the athletes’ requirements to meet Phase 3b goals. (MAS=maximum aerobic speed).
In (Image 1 and 2) is shown the physical conditioning process through the 3 different phases carefully in line with the rehabilitation timeline to ensure a safe and continuous progress for the athlete from low impact to running.
CONCLUSION
In Aspetar we see the early integration of conditioning after ACL injury as a vital component of the rehabilitation process to minimise deconditioning. The whole body must be targeted to better prepare the athlete physically and psychologically for the sport specific rehabilitation in preparation for return to play. Proper implementation of a post-injury training program requires regular assessment of the athlete, an understanding of the conditioning requirements of their sport and implementation training strategies that complement the recovery and rehabilitation of the injured limb. A well-designed conditioning program can prepare an athlete mentally and physically to optimize return to performance and complement the development of other physical qualities throughout the rehabilitation process.
Gergely Kis
Physical Coach
Aspetar Orthopaedic & Sports Medicine Hospital
Doha, Qatar
Contact: gergely.kis@aspetar.com
References
1. Mujika, I. & Padilla, S. Detraining: loss of a training induced physiological and performance adaptations (2000a). Part I. Sports Medicine, 30, 79-87
2. Myklebust G, Bahr R. Return to play guidelines after anterior cruciate ligament surgery (2005). British Journal of Sports Medicine 39(3):127-31
3. Ross A., Leveritt M. Long-Term Metabolic and Skeletal Muscle Adaptations to Short-Sprint Training (2001). Sports Medicine 31(15):1063-82
4. Olivier, N., Weissland, T., Legrand, R., Berthoin, S., Rogez, J., Thevenon, A. & Prieur, F. (2010). The effect of a one-leg cycling aerobic training program during the rehabilitation period in soccer players with anterior cruciate ligament reconstruction. Clinical Journal of Sport Medicine, 20, 28-33.
5. Figoni, S.F. Perspectives on cardiovascular 6tness and SCI. Journal of the American Paraplegia Society (1990). 13, 63-71.
6. Secher, N.H. & Volianitis, S. Are the arms and legs in competition for cardiac output? (2006). Medicine and Science in Sports and Exercise, 38, 1797- 1803.
7. Mujika I., Padilla S. Detraining: loss of training-induced physiological and performance adaptations. Part IIS (2000b). Sport Medicine, 30, 145–154. 10.216
8. Wall B., Dirks M. Skeletal muscle atrophy during short-term disuse: Implications for age-related sarcopenia (2013). Ageing Research Reviews. Volume 12, Issue 4, September 2013, Pages 898-906
9. Garber C. E., Blissmer B., Deschenes M. R., Franklin B. A., Lamonte M. J., Lee I.-M., et al.. (2011). Quantity and quality of exercise for developing and maintaining cardiorespiratory, musculoskeletal, and neuromotor fitness in apparently healthy adults. Med. Sci. Sport. Exerc. 43, 1334–1359. 10.1249
10. Grant J. Updating Recommendations for Rehabilitation after ACL Reconstruction: a Review. Clinical Journal of Sport Medicine (2013) 23(6):501-2
11. Buckthorpe M. Optimising the late-stage rehabilitation and return-to-sport training and testing process after ACL reconstruction. Sports Med. 2019;49(7):1043–58.
12. Bampouras TM, Marrin K, Sankey SP, and Jones PA. Test-retest reliability and sensitivity of the Concept2 Dyno dynamometer: practical applications. J Strength Cond Res 28(5):1381-1385, 2014
13. Graham-Smith P, Burgess K, and Ridler A. The relationship between strength, power, flexibility, anthropometry and technique and 2000m and 5000m roweing ergometer performance. In: Kinantropometry X. M. Marfell-Jones and T.Olds, eds New York: Routledge, 2007. Pp. 135-150
14. Jones Pand Bampouras, TM. A comparison of isokinetic and functional methods of assessing bilateral strength impalance. J Strength Cond Res 24: 1553-1558, 2010
15. Bentley DJ, Newell J, Bishop D (2007). "Incremental exercise test design and analysis: implications for performance diagnostics in endurance athletes". Sports Med. 37 (7): 575–86.
Header image by Rugby Club Arpajon Veinazès © Sylvie Moreau