Prevention of disuse muscular weakness by restriction of blood flow

PURPOSE: The aim of the present study was to compare the effects of periodic restriction of blood flow to lower extremities with those of isometric exercise on disuse muscular atrophy and weakness induced by immobilization and unloading. METHODS: The left ankle of each of 15 healthy males was immobilized for 2 wk using cast, and subjects were instructed to walk using crutches with non-weight bearing during this period. Subjects were divided into three groups: a restriction of blood flow (RBF) group (application of external compressive force of 200 mm Hg for 5 min followed by 3 min of rest, repeated five times in a single session, two sessions per day for 14 d); an isometric training (IMT) group (20 "exercises" of 5-s isometric contraction of the knee extensor, flexor, and ankle plantar flexor muscles followed by rest, twice a day, daily for 2 wk); and a control (CON) group (no intervention). We measured changes in muscle strength, thigh/leg circumferences, and serum growth hormone levels. RESULTS: Immobilization/unloading resulted in significant decreases in muscle strength of knee extensor and flexor muscles (P < 0.01 and < 0.05, respectively) and thigh and leg circumferences (P < 0.05, each) in the CON group, and significant decreases in muscle strength of the knee flexor muscles, ankle plantar flexor muscles, and leg circumference (P < 0.05) in the IMT group. RBF protected against these changes in muscle strength and thigh/leg circumference (P < 0.01 and < 0.05, respectively). No changes in serum growth hormone levels were noted. CONCLUSION: Our results indicate that repetitive restriction of blood flow to the lower extremity prevents disuse muscular weakness.     

Spine kinematics and trunk muscle activity during bipedal standing using unstable footwear

The current study was conducted to evaluate the effects of unstable footwear on spine kinematics and trunk muscle activity during bipedal stance. Therefore, spinal alignment and concurrent angular velocity measures were assessed in 27 asymptomatic adults while standing with unstable Masai Barefoot Technology (MBT) shoes and standard footwear, respectively, employing a multisegmental three‐dimensional trunk model. Electromyographic (EMG) analyses included recordings of the rectus abdominis, internal oblique, external oblique, upper thoracic paraspinals, lower thoracic erector spinae, and lumbar erector spinae. Kinematic and EMG variables were compared for the two shoe conditions via paired Student's t‐tests (α = 0.05). Results showed that wearing unstable MBT shoes increased flexion at the mid‐thoracic level (0.8°; P = 0.001) and led to greater mean velocities of angular displacement at the thoracolumbar (11.2%; P = 0.003) and at the lumbopelvic (10.8%; P = 0.02) regions, accompanied by more lumbar erector spinae activity (18.2%; P = 0.003). Accordingly, using MBT shoes may have potential implications in promoting spine tissue health, notably at the low back area, through expected improvements in terms of muscle conditioning and/or motor performance. However, additional investigations are warranted to further examine the framework of unstable footwear constructions within prevention and rehabilitation settings.     

Lower extremity joint loading during level walking with Masai barefoot technology shoes in overweight males

The purpose of this study was to evaluate the effects of Masai barefoot technology (MBT) shoes on lower extremity joint loading in overweight males during level walking. Therefore, lower extremity kinematics, kinetics, and muscle electromyographic signals of the vastus lateralis (VL), biceps femoris (BF), and gastrocnemius medialis (GM) were recorded in 10 overweight males at a self‐chosen walking speed with MBT shoes and conventional shoes. Selected peak joint moments, maximal joint force loading rates, mean muscle intensities, and co‐activation indices of the VL/BF, as well as of the VL/GM were analyzed and compared for the two shoe conditions using paired Student's t‐tests (α=0.05). Results showed that walking with MBT shoes reduced first peak knee adduction moments in overweight subjects. During midstance and terminal stance, increases in VL/GM co‐activation, accompanied by increases in VL and GM (only terminal stance) intensities were found for the MBT situation. Kinetic variables analyzed to assess ankle and hip joint loading did not exhibit any statistical differences. These results suggest that using MBT shoes diminishes medial compartment loads at the knee without overloading hip or ankle joints in overweight males. However, the additional muscle loading should not be overlooked, and warrants further investigation.     

Is motivation for marathon a protective factor or a risk factor of injury?

This research investigated whether and how self‐determined motivation predicts perceived susceptibility to injury during competition (marathon). Two correlational studies including 378 (Study 1) and 339 (Study 2) marathon runners were conducted. Participants filled out a questionnaire the day before the race measuring self‐determined motivation, perceived susceptibilities to marathon‐related injury and to keep running through pain, and control variables. Study 1 showed that self‐determined motivation was negatively related to perceived susceptibility to marathon‐related injury. Study 2 replicated this finding and showed that this relationship was partially mediated by perceived susceptibility to keep running through pain during the race. Moreover, results indicated that the predictive role of self‐determination was mostly driven by controlled forms of motivation, and more particularly external regulation. These results suggest that self‐determined motivation for sport is a protective factor of injury.     

Short-term immobilization after eccentric exercise. Part I: contractile properties

PURPOSE: The purpose of this study was to examine the compound muscle action potential (M-wave) and evoked contractile properties of immobilized muscle after high-force eccentric exercise. We believed that changes in these variables would contribute to the enhanced recovery of maximal voluntary force observed after short-term immobilization of damaged muscle. We hypothesized that immobilization after eccentric exercise would result in an enhanced M-wave and a change in contractile properties toward characteristics of faster muscle fibers. METHODS: Twenty-five college-age males were matched according to force loss after 50 maximal eccentric contractions of the elbow flexors and placed into an immobilization (IMM, N = 12) or control (CON, N = 13) group. IMM had their arm immobilized at 90 degrees and secured in a sling during a 4-d treatment. Maximal isometric torque (MVC) was assessed at baseline and for 8 d after treatment. M-wave and evoked contractile properties of the muscle (twitch torque [TT], maximal rate of torque development [MRTD], time to peak torque [TPT], and one-half relaxation time [HRT]) were assessed at baseline and for the first 5 d after treatment. RESULTS: Immediately postexercise, MVC was reduced 43% and 42% in IMM and CON, respectively. Recovery of MVC was significantly greater in IMM during recovery (P < 0.05), 95% of baseline MVC compared with 83% in CON. M-wave was reduced 32%, and all contractile properties were altered immediately postexercise. M-wave, MRTD, TPT, and HRT were not significantly different between groups during recovery (P > 0.05). TT demonstrated enhanced recovery in IMM (P < 0.05). CONCLUSIONS: Short-term immobilization after eccentric exercise resulted in enhanced recovery of maximal voluntary force. However, enhanced force recovery cannot be explained by muscle activation and evoked contractile properties of the muscle.     

Altering muscle activity in the lower extremities by running with different shoes

PURPOSE: To provide evidence that lower-extremity muscle activity during running is tuned in response to the loading rate of the impact forces at heel-strike. METHODS: Six runners ran two 30-min trials per week for 4 wk. The trials tested two shoes which differed only in the material hardness of the midsole. The shoes were tested in a randomized sequence. Bipolar surface EMG was recorded from the muscles of the rectus femoris, biceps femoris, medial gastrocnemius, and tibialis anterior. EMG was resolved into time-frequency space using wavelet techniques. EMG was analyzed for the 150 ms time window immediately before heel-strike. RESULTS: The intensity of the EMG and the ratio of the EMG intensity between high and low frequency components both showed significant changes between shoes, subjects, and muscles. Additionally, the intensity ratio showed a significant change over the course of each 30-min run. CONCLUSIONS: Lower-extremity muscle activity used to tune the muscles for the impact task can be altered by changing the material hardness of the shoe. The changes in the EMG frequency ratio suggest that muscle fiber-type recruitment patterns can also be altered by the choice of midsole material.     

Influence of shoe midsole hardness on plantar pressure distribution in four basketball-related movements

This study examined how shoe midsole hardness influenced plantar pressure in basketball-related movements. Twenty male university basketball players wore customized shoes with hard and soft midsoles (60 and 50 Shore C) to perform four movements: running, maximal forward sprinting, maximal 45° cutting and lay-up. Plantar loading was recorded using an in-shoe pressure measuring system, with peak pressure (PP) and pressure time integral (PTI) extracted from 10 plantar regions. Compared with hard shoes, subjects exhibited lower PP in one or more plantar regions when wearing the soft shoes across all tested movements (Ps < 0.05). Lower PTI was also observed in the hallux for 45° cutting, and the toes and forefoot regions during the first step of lay-up in the soft shoe condition (Ps < 0.05). In conclusion, using a softer midsole in the forefoot region may be a plausible remedy to reduce the high plantar loading experienced by basketball players.     

Lower limb muscle injury location shift from posterior lower leg to hamstring muscles with increasing discipline-related running velocity in international athletics championships

ObjectiveTo analyse the rates of lower limb muscle injuries in athletics disciplines requiring different running velocities during international athletics championships.DesignProspective total population study.MethodsDuring 13 international athletics championships (2009–2019) national medical teams and local organizing committee physicians daily reported all newly incurred injuries using the same study design, injury definition and data collection procedures. In-competition lower limb muscle injuries of athletes participating in disciplines involving running (i.e. sprints, hurdles, jumps, combined events, middle distances, long distances, and marathon) were analysed.ResultsAmong the 12,233 registered athletes, 344 in-competition lower limb muscle injuries were reported (36% of all in-competition injuries). The proportion, incidence rates and injury burden of lower limb muscles injuries differed between disciplines for female and male athletes. The most frequently injured muscle group was hamstring in sprints, hurdles, jumps, combined events and male middle distances runners (43–75%), and posterior lower leg in female middle distances, male long distances, and female marathon runners (44–60%). Hamstring muscles injuries led to the highest burden in all disciplines, except for female middle distance and marathon and male long distance runners. Hamstring muscles injury burden was generally higher in disciplines requiring higher running velocities, and posterior lower leg muscle injuries higher in disciplines requiring lower running velocities.ConclusionsThe present study shows discipline-specific injury location in competition context. Our findings suggest that the running velocity could be one of the factors that play a role in the occurrence/location of muscle injuries.     

The influence of heel height on lower extremity kinematics and leg muscle activity during gait in young and middle-aged women

The aim of this study was to evaluate the changes in electromyographic (EMG) activity of the lower limb muscles, and hip, knee and ankle kinematics during gait while wearing low- (4-cm) and high-heeled (10-cm) shoes in 31 young and 15 middle-aged adult women. We observed an increase in knee flexion and decrease in ankle eversion associated with elevated heel heights suggesting that compensatory mechanisms attenuating ground reaction forces may be compromised during gait with higher-heeled shoes. Additionally, we observed increased muscle activity during high-heeled gait that may exacerbate muscle fatigue. Collectively, these findings suggest that permanent wearing of heeled footwear could contribute to muscle overuse and repetitive strain injuries.     

骨骼肌急性拉伤后牵张训练对其材料力学性能影响的实验研究

目的:探讨牵张训练对骨骼肌急性拉伤后恢复期材料力学性能影响的规律.方法:92只SD大鼠为实验对象,选取10只为空白对照组,其余82只在同等条件下对其小腿三头肌实施急性拉伤后,随机分为实验对照组、牵张组和跑动组.于不同恢复期取腓肠肌进行拉伸测试,获取试样的拉伸极限张力-时间曲线,计算其应力、应变及弹性模量.结果:(1)极限应力:伤后第10天,牵张组和跑动组小腿三头肌的极限应力明显高于实验对照组(P<0.05);伤后第17天,牵张组小腿三头肌的极限应力恢复值最高(PPT-EC<0.05).(2)极限应变:肌肉伤后第30天实验对照组小腿三头肌极限应变仅为正常肌肉的85.93%(P<0.01);伤后第10天牵张组肌肉极限应变为正常肌肉的98.19%,第17天则明显高于正常肌肉(P<0.01);跑动组伤后第10天也明显恢复(P<0.01).(3)杨氏模量:牵张对肌肉的模量的影响较自然修复及跑动训练均更明显.结论:急性拉伤肌肉抗拉性能基本恢复约需3周,应变恢复相对较慢.牵张对肌肉伤后的材料力学性能有积极的影响,但以影响应变性能和优化模量为主.肌肉急性拉伤后进行适量的跑动对肌肉的材料力学性能有积极作用,大强度跑动致重复性损伤的可能性加大.     

Progressive resistance training temporarily alters hamstring torque-angle relationship

To examine the effects of eccentric and concentric progressive resistance training on muscle torque-angle relationship, 30 young adults were randomly allocated into three groups of 10, control (CTL), eccentric training (ECC) and concentric training (CON). The ECC and CON groups performed seven sessions over 3 weeks of progressive resistance training of the right hamstrings muscle, using a standard barbell and a leg curl machine. Torque-angle relationship was measured before and 4, 11 and 18 days after the end of training. Voluntary isometric torque was recorded at seven test angles, with the subject prone (20-80 degrees; 0 degrees is full extension). In the CON group, the angle of peak isometric torque increased from 46.0 +/- 5.2 degrees pre-training to 53.0 +/- 14.9 degrees on day 4 following training (P<0.05). In the ECC group, peak torque was increased over baseline on days 4 and 11 post-training, particularly at extended knee angles (P<0.05). The angle at which peak torque occurred was decreased on day 4 (50.0 +/- 8.2 degrees pre-training, 29.0 +/- 7.4 degrees on day 4) and on day 11 (both P<0.01), but was similar to baseline 18 days after training. ECC therefore induced a temporary change in torque-angle relationship.     

The Physiology of Marathon Running

In brief: The marathon is one of the greatest tests of human endurance. This review article describes the physiological demands and responses of the respiratory, cardiovascular, and muscular systems to marathon running, focusing on the chain of oxygen transport needed to fulfill the aerobic requirements of marathon running. During the race, runners use about 75% of VO₂ max. Increased levels of ventilation (> 80 liters· min^?1) have been observed during the marathon. This can lead to decrements in forced vital capacity and respiratory muscle fatigue. Prolonged muscle activity during the run can cause muscle injury such as inflammation and necrosis of muscle fibers. Techniques for augmenting performance include endurance and interval training, diet manipulation, and racing strategy.     

The effect of heavy strength training on muscle mass and physical performance in elite cross country skiers

Aim: To investigate the effect of supplementing high‐volume endurance training with heavy strength training on muscle adaptations and physical performance in elite cross country skiers. Eleven male (18–26 years) and eight female (18–27 years) were assigned to either a strength group (STR) (n=9) or a control group (CON) (n=10). STR performed strength training twice a week for 12 weeks in addition to their normal endurance training. STR improved 1 repetition maximum (RM) for seated pull‐down and half squat (19±2% and 12±2%, respectively), while no change was observed in CON. Cross‐sectional area (CSA) increased in m. triceps brachii for both STR and CON, while there was no change in the m. quadriceps CSA. VO_2max during skate‐rollerskiing increased in STR (7±1%), while VO_2max during running was unchanged. No change was observed in energy consumption during rollerskiing at submaximal intensities. Double‐poling performance improved more for STR than for CON. Both groups showed a similar improvement in rollerski time‐trial performance. In conclusion, 12 weeks of supplemental heavy strength training improved the strength in leg and upper body muscles, but had little effect on the muscle CSA in thigh muscles. The supplemental strength training improved both VO_2max during skate‐rollerskiing and double‐poling performance.     

Whole‐body vibration training increases muscle strength and mass in older women: a randomized‐controlled trial

To determine whether 10 weeks of whole‐body vibration (WBV) training has a significant effect on strength, muscle mass, muscle power, and mobility in older women, 26 subjects were randomly assigned to a WBV training group (n=13; mean age 79 years) and a control (CON) group (n=13; mean age 76 years). Maximal voluntary isometric contraction (MVIC) increased 38.8% in the WBV group, without changes in the CON group. Electromyographic activity of the vastus medialis (VM), the vastus lateralis, and the biceps femoris (BF) did not change in either group. Thigh muscle cross‐sectional area increased significantly after training in VM (8.7%) and BF (15.5%). Muscle power at 20%, 40%, and 60% MVIC decreased from pre‐test to post‐test in the CON group; however, WBV training prevented the decrease in the WBV group. Consequently, mobility, measured by the Timed Up and Go test, increased significantly after training (9.0%) only in the WBV group. Ten weeks of lower limb WBV training in older women produces a significant increase in muscle strength induced by thigh muscle hypertrophy, with no change in muscle power. The adaptations to WBV found in the present study may be of use in counteracting the loss of muscle strength and mobility associated with age‐induced sarcopenia.     

Inflammation and atrial remodeling after a mountain marathon

Endurance athletes have an increased risk of atrial fibrillation. We performed a longitudinal study on elite runners of the 2010 Jungfrau Marathon, a Swiss mountain marathon, to determine acute effects of long‐distance running on the atrial myocardium. Ten healthy male athletes were included and examined 9 to 1 week prior to the race, immediately after, and 1, 5, and 8 days after the race. Mean age was 34.9 ± 4.2 years, and maximum oxygen consumption was 66.8 ± 5.8 mL/kg*min. Mean race time was 243.9 ± 17.7 min. Electrocardiographic‐determined signal‐averaged P‐wave duration (SAPWD) increased significantly after the race and returned to baseline levels during follow‐up (128.7 ± 10.9 vs. 137.6 ± 9.8 vs. 131.5 ± 8.6 ms; P < 0.001). Left and right atrial volumes showed no significant differences over time, and there were no correlations of atrial volumes and SAPWD. Prolongation of the SAPWD was accompanied by a transient increase in levels of high‐sensitivity C‐reactive protein, proinflammatory cytokines, total leucocytes, neutrophil granulocytes, pro atrial natriuretic peptide and high‐sensitivity troponin. In conclusion, marathon running was associated with a transient conduction delay in the atria, acute inflammation and increased atrial wall tension. This may reflect exercise‐induced atrial myocardial edema and may contribute to atrial remodeling over time, generating a substrate for atrial arrhythmias.     

Pre-race dietary carbohydrate intake can independently influence sub-elite marathon running performance

We examined whether selected anthropometric and nutritional factors influenced field-based marathon running performance. An internet-based data collection tool allowed competitors in the 2009 London Marathon (n=257, mean ± SD age: 39 ± 8 years, finish time: 273.8 ± 59.5 min) to record a range of anthropometric, training and nutritional predictors. Multivariate statistical methods were used to quantify the change in running speed mediated by a unit change in each predictor via the 95% confidence interval for each covariate-controlled regression slope ( B). Gender ( B=1.22 to 1.95 km/h), body mass index ( B=-0.14 to -0.27 km/h), training distance ( B=0.01 to 0.04 km/h) and the amount of carbohydrate consumed the day before the race ( B=0.08 to 0.26 km/h) were significant predictors, collectively accounting for 56% of the inter-individual variability in running speed (P<0.0005). Further covariate-adjusted analysis revealed that those competitors who consumed carbohydrate the day before the race at a quantity of >7 g/kg body mass had significantly faster overall race speeds (P=0.01) and maintained their running speed during the race to a greater extent than with those who consumed <7 g/kg body mass (P=0.02). We conclude that, in addition to gender, body size and training, pre-race day carbohydrate intake can significantly and independently influence marathon running performance.     

Long-term effects of shoe mileage on knee and ankle joints muscle co-contraction during walking in females with genu varus

BackgroundShoe mileage may influence the risk of sustaining injuries during walking.Research questionWhat are the effects of shoe mileage on knee and ankle muscle co-contraction during walking in females with genu varus?MethodsFifteen healthy and 15 women diagnosed with genu varus received a new pair of running shoes. They were asked to wear these shoes over 6 months. Pre and post intervention, muscle activities of the dominant limb were recorded during a walking test at preferred gait speed. Two dependent variables were assessed to examine muscle co-contraction: (1) directed co-contraction ratios of agonists and antagonists, and (2) general joint muscle co-contraction.FindingsResults demonstrated significant main effects of the “shoe” factor for general ankle co-contraction during the push-off phase (p = 0.013, d = 1.503). Irrespective of experimental group, paired comparisons revealed significantly lower general ankle co-contraction during the push-off phase after the intervention. A significant main effects of “shoe” for general knee co-contraction during loading phase (p = 0.025, d = 0.895) was also observed. In both groups, paired comparison revealed significantly lower general knee co-contraction during the push-off phase in the post condition. We did not find any significant main effect of group nor group-by-shoe interaction for general ankle co-contraction during the stance phase. Likewise, we did not observe any significant main effect of “shoe”, “group” and “group-by-shoe” interaction for mediolateral directed knee co-contraction during stance phase of walking (p > 0.05).SignificanceOur findings showed that the shoe mileage but not the genu varus condition affects the general and directed co-contraction of the muscles stabilizing the knee and ankle joints. Together with the observed findings on ankle and knee muscle co-contraction, it is essential to change running shoes after a long wearing time in both healthy and genu varus females.     

Fatigue and recovery at long and short muscle lengths after eccentric training

PURPOSE: To determine the effects of high-speed eccentric training of rat plantar flexor muscles on: 1) maximum (120 Hz) force at 90 degrees ankle position; 2) fatigue (40 concentric muscle actions, ROM 50 degrees) and recovery (6 concentric muscle actions) tested at short or long muscle lengths; and 3) low-frequency fatigue. METHODS: Training consisted of eccentric muscle actions from ankle positions of 140 degrees to 40 degrees (velocity approximately 400 degrees x s(-1)) followed by unresisted concentric muscle actions (5 x 10 repetitions, 5 d x wk(-1) for 6 wk). Fatigue was induced by concentric muscle actions with a rest of 12.5 s between muscle actions, and recovery consisted of equivalent concentric muscle actions performed every 5 min for 30 min. Low-frequency fatigue was measured 35 min after testing at 90 degrees ankle position by using the ratio of isometric force produced by 20- and 100-Hz stimulation frequencies. RESULTS: Eccentric training increased maximal isometric force per muscle weight by 22% whereas muscle weights were unchanged. In control muscles (C), isometric force immediately preceding each concentric muscle action decreased more at long lengths than at short lengths during the fatigue protocol; this length-dependent difference disappeared after 30 min of recovery. At short lengths, isometric force decreased less in trained muscles (T) (C: 78.4 +/- 3.6%; T: 59.6 +/- 4.4%) and recovered more during the following 30-min period (C: 84.7 +/- 2.5%; T: 95.4 +/- 2.8% of initial values). Changes in F20/F100 were smaller for trained muscles (C: 35.4 +/- 2.0%; T: 22.0 +/- 1.4%). CONCLUSIONS: High-speed eccentric training (5 d x wk(-1) for 6 wk) reduced fatigability and enhanced recovery mainly at long muscle lengths. It also reduced low-frequency fatigue, which may be attributed to alterations in intracellular calcium handling.     

Serum electrolytes in Ironman triathletes with exercise-associated muscle cramping

PURPOSE: To compare serum electrolyte concentrations of cramping and control Ironman triathletes. METHODS: Triathletes suffering from acute exercise-associated muscle cramping (EAMC) after the 2000 South African Ironman Triathlon formed the cramping group (CR, N = 11). Non-cramping triathletes matched for race finishing time and body mass formed the control group (CON, N = 9). All subjects were weighed at race start and immediately post-race. Blood samples were drawn from both groups during recovery for the analysis of serum magnesium, glucose, sodium, potassium and chloride concentrations. Hemoglobin concentration and hematocrit were also measured. Surface electromyography (EMG) (mV) was recorded from a non-cramping control muscle (triceps) and the most severely cramping lower limb muscle of the CR group. EMG was recorded at the beginning of every minute for a 10-min period during recovery. RESULTS: There were no significant differences between the groups for body mass or percent body mass loss during the race. Post-race sodium concentration was significantly lower (P = 0.01) in the CR group than the CON group (140 +/- 2 vs 143 +/- 3 mmol.L) but was within the normal clinical range of post-race serum sodium concentrations. There were no significant differences between the two groups for post-race serum electrolytes, glucose, hemoglobin concentrations or hematocrit. Surface EMG (mV) was significantly higher (P < 0.05) in the cramping muscles than the control muscle of the CR group at 0, 3, 4, and 5 min of the 10-min recording period. CONCLUSION: Acute EAMC in ironman triathletes is not associated with a greater percent body mass loss or clinically significant differences in serum electrolyte concentrations. The increased EMG activity of cramping muscles may reflect increased neuromuscular activity.     

Scheduling of eccentric lower limb injury prevention exercises during the soccer micro‐cycle: Which day of the week?

Scheduling eccentric‐based injury prevention programs (IPP ) during the common 6‐day micro‐cycle in soccer is challenged by recovery and tapering phases. This study profiled muscle damage, neuromuscular performance, and perceptual responses to a lower limb eccentric‐based IPP administered 1 (MD +1) vs 3 days (MD +3) postmatch. A total of 18 semi‐professional players were monitored daily during 3 in‐season 6‐day micro‐cycles, including weekly competitive fixtures. Capillary creatine kinase concentration (CK ), posterior lower limb isometric peak force (PF ), counter‐movement jump (CMJ ) performance, and muscle soreness were assessed 24 hours prior to match‐day (baseline), and every 24 hours up to 120 hours postmatch. The IPP consisted of lunges, single stiff leg dead‐lifts, single leg‐squats, and Nordic hamstring exercises. Performing the IPP on MD +1 attenuated the decline in CK normally observed following match play (CON : 142%; MD +3: 166%; small differences). When IPP was delivered on MD +3, CK was higher vs CON and MD +1 trials on both MD +4 (MD +3: 260%; CON : 146%; MD +1: 151%; moderate differences) and MD +5 (MD +3: 209%; CON : 125%; MD +1: 127%; small differences). Soreness ratings were not exacerbated when the IPP was delivered on MD +1, but when prescribed on MD +3, hamstring soreness ratings remained higher on MD +4 and MD +5 (small differences). No between‐trial differences were observed for PF and CMJ . Administering the IPP in the middle of the micro‐cycle (MD +3) increased measures of muscle damage and soreness, which remained elevated on the day prior to the next match (MD +5). Accordingly, IPP should be scheduled early in the micro‐cycle, to avoid compromising preparation for the following match.