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Strength and Power Training in Rehabilitation: Underpinning Principles and Practical Strategies to Return Athletes to High Performance

DOI:10.1007/s40279-019-01195-6
Authors:
Luca Maestroni at Middlesex University, UK
Luca Maestroni
Paul Read at University College London
Paul Read
Chris Bishop at Middlesex University, UK
Chris Bishop
Anthony N Turner at Middlesex University, UK
Anthony N Turner
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Abstract and Figures

Injuries have a detrimental impact on team and individual athletic performance. Deficits in maximal strength, rate of force development (RFD), and reactive strength are commonly reported following several musculoskeletal injuries. This article first examines the available literature to identify common deficits in fundamental physical qualities following injury, specifically strength, rate of force development and reactive strength. Secondly, evidence-based strategies to target a resolution of these residual deficits will be discussed to reduce the risk of future injury. Examples to enhance practical application and training programmes have also been provided to show how these can be addressed.
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Vol.:(0123456789)
Sports Medicine (2020) 50:239–252
https://doi.org/10.1007/s40279-019-01195-6
REVIEW ARTICLE
Strength andPower Training inRehabilitation: Underpinning
Principles andPractical Strategies toReturn Athletes toHigh
Performance
LucaMaestroni1,2 · PaulRead3· ChrisBishop4· AnthonyTurner4
Published online: 26 September 2019
© Springer Nature Switzerland AG 2019
Abstract
Injuries have a detrimental impact on team and individual athletic performance. Deficits in maximal strength, rate of force
development (RFD), and reactive strength are commonly reported following several musculoskeletal injuries. This article first
examines the available literature to identify common deficits in fundamental physical qualities following injury, specifically
strength, rate of force development and reactive strength. Secondly, evidence-based strategies to target a resolution of these
residual deficits will be discussed to reduce the risk of future injury. Examples to enhance practical application and training
programmes have also been provided to show how these can be addressed.
* Luca Maestroni
lucamae@hotmail.it
Paul Read
paul.read@aspetar.com
Chris Bishop
c.bishop@mdx.ac.uk
Anthony Turner
a.n.turner@mdx.ac.uk
1 Smuoviti, Viale Giulio Cesare, 29, 24121Bergamo, BG,
Italy
2 StudioErre, Via della Badia, 18, 25127Brescia, BS, Italy
3 Athlete Health andPerformance Research Center, Aspetar
Orthopaedic andSports Medicine Hospital, Doha, Qatar
4 London Sport Institute, School ofScience andTechnology,
Middlesex University, Greenlands Lane, London, UK
Key Points
Residual deficits in maximal strength, rate of force devel-
opment and reactive strength are documented following
musculoskeletal injury.
Targeting these residual deficits following injury can
reduce the risk of future injury as a means of tertiary
prevention.
Rehabilitation should prepare athletic populations to
tolerate loads and velocities across the full spectrum of
the force–velocity curve and this is essential for return-
ing injured athletes to high performance levels.
1 Introduction
Injuries have a detrimental impact on team and individual
athletic performance, with increased player availability
improving the chances of success [1]. The available data
suggest an interaction between injury, performance, physi-
cal outputs, and success at both team and individual levels
[2–4]. It seems logical that all staff involved should strive
to work together in an interdisciplinary fashion to prevent
injuries and to improve performance. Furthermore, several
studies have reported that a previous injury may increase the
risk for subsequent injuries [5–10]. This raises the question
of whether persistent deficits have been fully assessed and
targeted before athletes return to play (RTP), and if a greater
emphasis should be placed on a return to performance strat-
egy as a means of tertiary prevention [11].
Following the occurrence of injury or pain onset, defi-
cits in strength [12–16], strength ratios [17], rate of force
development [18–23], reactive strength [24–26], leg stiff-
ness [27–31], and peak power [32–34], have all been shown
in athletic populations. Equally, these same attributes are
widely considered important physical performance deter-
minants in high-performance sport [35, 36]. In spite of this,
rehabilitation programmes often adopted in research and
clinical practice are mainly focused on restoring strength
[37–40], which by definition, consists of high forces at low
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... This work could help optimize interventions to address lingering motor control deficits despite current recommended clinical practice. Interestingly, strength training literature has shown that training with heavy loads (>80% of 1 repetition maximum) increased neural drive; in addition, intent to move weight quickly and ballistic power training methods have helped increase rate of force development by lowering MU recruitment thresholds (43). Such interventions could be considered to determine utility to address AMI in both ipsilateral and contralateral limbs after ACL injury. ...
Arthrogenic muscle inhibition after anterior cruciate ligament injury: Injured and uninjured limb recovery over time
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Introduction It is well documented that marked weakness of the quadriceps is present after knee joint injury. This joint trauma induces a presynaptic reflex inhibition of musculature surrounding the joint, termed arthrogenic muscle inhibition (AMI). The extent to which anterior cruciate ligament (ACL) injury affects thigh musculature motor unit activity, which may affect restoration of thigh muscle strength after injury, is undetermined. Methods A randomized protocol of knee flexion and extension isometric contractions (10%–50% maximal voluntary isometric contraction) were performed for each leg on 54 subjects with electromyography array electrodes placed on the vastus medialis, vastus lateralis, semitendinosus, and biceps femoris. Longitudinal assessments for motor unit recruitment and average firing rate were acquired at 6-month intervals for 1 year post ACL injury. Results The ACL-injured population demonstrated smaller quadriceps and hamstrings motor unit size (assessed via motor unit action potential peak-to-peak amplitude) and altered firing rate activity in both injured and uninjured limbs compared to healthy controls. Motor unit activity remained altered compared to healthy controls at 12 months post ACL reconstruction (ACLR). Discussion Motor unit activity was altered after ACLR up to 12 months post-surgery. Further research is warranted to optimize rehabilitation interventions that adequately address altered motor unit activity and improve safety and success with return to sport after ACLR. In the interim, evidence based clinical reasoning with a focus on development of muscular strength and power capacity should be the impetus behind rehabilitation programming to address motor control deficits.
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... The available meta-analyses focused on the effects of PJT on vertical jump height (e.g., drop jump height) without assessing the specific effects of PJT on the RSI [33,34]. Similarly, previous reviews analysed training-induced effects on the RSI, although: (1) there was a focus on a myriad of strength and conditioning methods without examining single-mode PJT effects, (2) these studies examined specific populations (e.g., endurance runners; post-rehabilitation athletes; males), and (3) some studies were biased in their systematic review and/or meta-analytical approach (e.g., single-control group sample size not proportionately divided in studies including multiple-intervention groups) [2,21,[35][36][37][38][39][40][41]. Additionally, the potential role of moderators such as participants' sex, age, and sport, have not been addressed in a meta-analytical approach. ...
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... Physical inactivity is a consistent part of many people's daily life [1], as well as the possibility for prolonged phases of immobilization [2][3][4], which can have significant negative influences on metabolic and musculoskeletal health [5,6] in sports performance. In addition to injuries and frequent sitting, evidence highlights significantly decreased physical activity and motivation to train [7] in the majority of people due to the COVID-19 lockdown(s) [8][9][10]. ...
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Article
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... N respectively), there are hardly any variations in the inter-articular ratio (ER:IR = 0.65 dominant arm vs. 0.67 non-dominant arm) [17]. Despite all this, imbalances in force production are synonymous with a greater probability of suffering an injury [18]. ...
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Article
  • Dec 2018
Training frequency is considered an important variable in the hypertrophic response to regimented resistance exercise. The purpose of this paper was to conduct a systematic review and meta-analysis of experimental studies designed to investigate the effects of weekly training frequency on hypertrophic adaptations. Following a systematic search of PubMed/MEDLINE, Scoups, and SPORTDiscus databases, a total of 25 studies were deemed to meet inclusion criteria. Results showed no significant difference between higher and lower frequency on a volume-equated basis. Moreover, no significant differences were seen between frequencies of training across all categories when taking into account direct measures of growth, in those considered resistance-trained, and when segmenting into training for the upper body and lower body. Meta-regression analysis of non-volume-equated studies showed a significant effect favoring higher frequencies, although the overall difference in magnitude of effect between frequencies of 1 and 3+ days per week was modest. In conclusion, there is strong evidence that resistance training frequency does not significantly or meaningfully impact muscle hypertrophy when volume is equated. Thus, for a given training volume, individuals can choose a weekly frequency per muscle groups based on personal preference.
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What is the Impact of Muscle Hypertrophy on Strength and Sport Performance
Article
  • Dec 2018
ABSTRACT FOR DECADES, MOST SCIENTISTS AND PRACTITIONERS HAVE AGREED THAT MUSCLE HYPERTROPHY ALSO INDUCES STRENGTH GAINS. HOWEVER, A RECENT PUBLICATION “THE PROBLEM OF MUSCLE HYPERTROPHY: REVISITED,” BUCKNER, SL, DANKEL, SJ, MATTOCKS, KT, JESSEE, MB, MOUSER, JG, COUNTS, BR, ET AL. THE PROBLEM OF MUSCLE HYPERTROPHY: REVISITED. MUSCLE NERVE 54: 1012–1014, 2016, QUESTIONED THE MECHANISTIC ROLE THAT EXERCISE-INDUCED INCREASES IN MUSCLE SIZE HAVE ON THE EXERCISE-INDUCED INCREASES IN STRENGTH (OR FORCE PRODUCTION), AS WELL AS THE INFLUENCE THAT EXERCISE-INDUCED INCREASES IN STRENGTH HAVE ON SPORTS PERFORMANCE. SUCH SUGGESTIONS UNDERMINE THE IMPORTANCE OF CERTAIN ASPECTS OF STRENGTH AND CONDITIONING FOR SPORT. SPECIFICALLY, IF NOT ACTING AS A MECHANISM FOR STRENGTH ADAPTATION, IT IS UNCLEAR IF THERE IS A SPORTS-RELATED BENEFIT TO SKELETAL MUSCLE HYPERTROPHY. IN ADDITION, THE AUTHORS ARGUED THAT IF STRENGTH HAS LITTLE IMPACT ON SPORTS PERFORMANCE, STRENGTH AND CONDITIONING PROGRAMS MAY BE DOING LITTLE MORE THAN DELAYING RECOVERY FROM PRACTICING THE ACTUAL SPORT. THIS CONTENTION ALSO INDICATES THAT HYPERTROPHY SHOULD BE AVOIDED IN NEARLY ALL SCENARIOS BECAUSE INCREASED MUSCLE SIZE WOULD BE ADDITIONAL MASS THAT MUST BE OVERCOME. THE PURPOSE OF THIS SPECIAL DISCUSSION IS TO ALLOW FOR AN IN-DEPTH SCIENTIFIC DISCUSSION OF THE EXPERIMENTAL EVIDENCE FOR AND AGAINST THE POSITION OF BUCKNER ET AL. THAT EXERCISE-INDUCED INCREASES IN MUSCLE SIZE HAVE LITTLE RELEVANCE ON THE EXERCISE-INDUCED INCREASES IN STRENGTH, AND THUS, SPORT PERFORMANCE.
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Risk factors for patellofemoral pain: A systematic review and meta-analysis
Article
  • Sep 2018
Background Patellofemoral pain (PFP) is a prevalent condition commencing at various points throughout life. We aimed to provide an evidence synthesis concerning predictive variables for PFP, to aid development of preventative interventions. Methods We searched Medline, Web of Science and SCOPUS until February 2017 for prospective studies investigating at least one potential risk factor for future PFP. Two independent reviewers appraised methodological quality using the Newcastle–Ottawa Scale. We conducted meta-analysis where appropriate, with standardised mean differences (SMD) and risk ratios calculated for continuous and nominal scaled data. Results This review included 18 studies involving 4818 participants, of whom 483 developed PFP (heterogeneous incidence 10%). Three distinct subgroups (military recruits, adolescents and recreational runners) were identified. Strong to moderate evidence indicated that age, height, weight, body mass index (BMI), body fat and Q angle were not risk factors for future PFP. Moderate evidence indicated that quadriceps weakness was a risk factor for future PFP in the military, especially when normalised by BMI (SMD −0.69, CI −1.02, –0.35). Moderate evidence indicated that hip weakness was not a risk factor for future PFP (multiple pooled SMDs, range −0.09 to −0.20), but in adolescents, moderate evidence indicated that increased hip abduction strength was a risk factor for future PFP (SMD 0.71, CI 0.39, 1.04). Conclusions This review identified multiple variables that did not predict future PFP, but quadriceps weakness in military recruits and higher hip strength in adolescents were risk factors for PFP. Identifying modifiable risk factors is an urgent priority to improve prevention and treatment outcomes.
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The Effect of Isometric Exercise on Pain in Individuals with Plantar Fasciopathy: a randomised crossover trial
Article
  • Sep 2018
Isometric exercise is commonly recommended for immediate pain relief in individuals suffering from lower limb tendinopathies, despite the limited evidence supporting its analgesic effect. Due to the similarities between plantar fasciopathy and tendinopathies, the aim of this trial was to investigate the acute effect of isometric exercise on pain, compared to isotonic exercise, or walking, in individuals with plantar fasciopathy. We recruited 20 individuals with plantar fasciopathy for this prospectively‐registered, participant‐blinded, randomised, superiority crossover trial (ClinicalTrials. gov: NCT03264729). Participants attended three exercise sessions (isometric, isotonic or walking) in a randomised order, within a two‐week period. Both isometric and isotonic exercises were performed standing with the forefoot on a step bench, while walking was performed barefoot. The primary outcome was pain (measured on a 0‐100mm VAS) during a pain‐aggravating activity. Secondary outcomes included pressure pain threshold (PPT) under the heel, and plantar fascia thickness (PFT). All outcomes were measured before and after each exercise session. There were no significant differences between the three exercises on pain (P=0.753), PPTs (P=0.837) or PFT (P=0.718). Further, there was no change in pain from before to after any of the exercises (isometric exercise 2.7mm (95%CI: ‐12.2; 6.8), isotonic exercise ‐3.4mm (95%CI: ‐5.0; 11.8) or walking 1.6mm (95%CI: ‐16.1; 12.9)). Contrary to expectations, isometric exercise was no better than isotonic exercise or walking at reducing pain in individuals with plantar fasciopathy. None of the exercises induced any systematic analgesic effect. This article is protected by copyright. All rights reserved.
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