Introduction

Photobiomodulation therapy (PBMT) or low-level laser therapy (LLLT) is the application of laser light to a pathologic tissue or condition by a means of a low-powered laser and/or light emitting diodes. PBMT causes a photochemical effect in which light is absorbed and induces chemical changes in tissues. PBMT is used to promote tissue regeneration, reduce inflammation and swelling, and relieve pain. The aim of this study was to determine effectiveness of PBMT and cryotherapy both isolated and combined following muscle fatigue from high-intensity exercise.

 Methods

• Forty volunteers, average age of 25.30 years old, were randomly divided into five groups: (1) placebo group (PG); (2) PBMT group (PBMT); (3) cryotherapy group (CG); (4) cryotherapy-PBMT group (CPG); and (5) PBMT-cryotherapy group (PCG)
• Volunteers subjected to a muscle fatigue-inducing protocol on the elbow flexors of their dominant upper extremity for four sessions
• Measures:
  • Maximal Voluntary Contractions (MVC) – measured prior to exercise, immediately post exercise, and at 24, 48, and 72 hours
  • Blood collection– was performed at initial session at the following intervals: pre-exercise, 5 min post exercise, and 60 min post exercise
  • In the remaining sessions performed 24, 48, and 72 h later, blood collection and isometric evaluation of MVC were repeated
• PBMT application: cluster of 69 LEDs held in direct contact with skin on muscle belly of biceps receiving a phototherapy with 41.7-J dose (30 s of irradiation) or 0 J for placebo group
• Cryotherapy application: thermal bags containing ice cubes fixed to biceps with compression in supine position for 20 minutes

Results

• Maximal Voluntary Contractions
  • Exercise led to significant decrease in production of MVC after fatigue protocol in all groups
  • After treatment (72 hours), significant increases in MVC capacity and decrease in DOMS of volunteers who received treatment with PBMT, CPG, and PCG, compared with the PG and CG group
  • CG showed no differences compared to PG
• Blood Collections Concentrations
  • Biochemical marker of oxidative damage to lipids (TBARS nmol/ml):
    • Significant decrease in TBARS concentrations in PBMT, CPG, and PCG, compared with the PG
    • In CG there was a significant decrease in TBARS concentrations at 1, 48, 72 h after treatment
  • Biochemical marker of oxidative damage to proteins (Carbonylated proteins; CP):
    • Significant decrease in PC concentrations in the PBMT, CG and PCG, compared with the PG
    • In the CPG, a significant decrease in PC concentrations in 24 to 72 h after treatment
  • Muscle damage (Creatine Kinase; CK)
    • 1-72 hours after treatment, significant decrease in CK shown PBMT compared with PG
    • PCG and CPG groups with significant decrease in CK 48 and 72 h after treatment respectively

 Discussion

• PBMT has considerable potential for prevention of muscle fatigue and damage caused by high-intensity exercise
• PBMT can improve performance when applied post-exercise for goal of muscle recovery
• Cryotherapy demonstrates some effect in reduction of markers of oxidative damage to lipids and proteins
• Cryotherapy has no influence on maintain MVC capacity
• Cryotherapy alone had no effect on muscle damage marker (CK), only in the group along with PBMT
• PBMT application exhibited significant improvement in MVC after 60 min after the application of the muscle recovery protocol

PTF Take Aways

• Cryotherapy associated with PBMT does not improve effects of PBMT, isolated application of PBMT seems to be the best option to improve muscle recovery in the long term and short term
• Cryotherapy in isolation is unable to provide muscle recovery

Does photobiomodulation therapy do better than cryotherapy in muscle recovery after a high-intensity exercise?A randomized, double-blind, placebo-controlled clinical trial. Lasers Med Sci (2017) 32:429–437.

Lumbar Flexion-Based Program

Low back pain is the most common condition treated by physical therapists. Research shows that progressive endurance and fitness exercises are helpful to reduce pain and increase function in patients with chronic low back pain. Additionally, interventions that include patient education regarding pain and counseling to maintain a physically active lifestyle are very valuable. For some patients with diagnoses such as lumbar stenosis, degenerative disk disease, or arthritis, a lumbar flexion program could be beneficial. Some examples of such exercises are listed below.

Beattie, Paul. The Lumbar Spine: Physical Therapy Patient Management Using Current Evidence. Current Concepts of Orthopedic Physical Therapy. 4^th Edition. Orthopedic Section, APTA, Inc. 2016.

Exercises

1. Single Knee to Chest
   • 3×30 seconds
   • 1x/day
2. Double Knee to Chest
   • 3×30 seconds
   • 1x/day
3. Seated Lumbar Stretch
   • 3×30 seconds
   • 1x/day
4. Bridging
   • 3×10
   • 1x/day
5. Cat/Cow
   • X20
   • 1x/day
6. Hip piriformis stretching
   • 3×30 seconds
   • 1x/day
7. Half Kneel Psoas Stretch
   • 3×30”
   • 1x/day
8. Child’s pose
   • 3×30”
   • 1x/day

Introduction

Skeletal muscle mass is a crucial factor for health, longevity, and maintaining the ability to complete activities of daily living, ambulate, and avoid falls. Muscle quantity and quality also directly impacts individuals in fitness and sport performance. A disuse of skeletal muscle can rapidly lead to atrophy of muscle tissue, resulting in reduced oxidation capacity, sarcomere shortening, and reduced muscle compliance. This in turn reduces exercise capacity, impairs the immune system, and decreases sensitivity to insulin.

Typically, high-intensity resistance training at 70-8% of a 1 repetition maximum (1-RM) is recommended to increase muscle mass and strength. However, this recommendation is often very challenging and even contraindicated for certain individuals such as those with underlying chronic medical conditions, rehabilitation patients, recovering athletes, or a post-operative population. Several studies have proposed the idea that Blood Flow Restricted (BFR) low load exercise (20-30% maximal capacity) may stimulate significant muscular adaptations, through use of an external constriction device. There has been a fast-growing body of literature for BFR training and the aim of this review is to systematically assess studies and identify which BFR training methods have the greatest results in strength and hypertrophy.

Methods

47 studies were identified to fit inclusion criteria of BFR with exercise stimulus compared to non BFR with exercise. Studies were required to include at least one of two outcomes: muscle strength or muscle size. These studies included all healthy participates with a mean age of 34. Studies were categorized into two exercise groups: aerobic and resistance training.

Results

Muscle Strength
The mean improvement in strength grains of experimental group with BFR aerobic exercise was 0.4nM above the strength changes in that of the control group. Training >6 weeks increased this mean difference to 0.6nM, compared to 0.2 nM in training <6 weeks. Typically, muscle strength in the BFR aerobic group was increased by 5-8 nM.

The mean improvement in strength gains of experiment group with BFR resistance exercise and control group was an additional 0.3 kg force. Gains in muscle strength were significantly greater when intensity of exercise was >20%1 RM versus <20% 1 RM. When comparing 20% 1 RM to 30% 1 RM, training at 30% 1 RM resulted in a much greater improvement in muscle strength. The mean difference between the experimental and control group were relatively small. Cuff pressure of >150 mmHG caused a greater increased in strength compared to cuff pressure <150 mmHg., 0.2 kg and 0.1 kg respectively.

Muscle hypertrophy
Aerobic training had a mean increase of post training muscle size of 0.32 cm^2 between control and experimental groups. The increase in size of muscle as a result of BFR Training was 0.41 cm^2 greater than that seen in the control groups.

Studies considering both modalities of exercise combined with BFR showed an increase in muscle size of 2-5 cm. Muscle size differences between the experimental and control group did vary when training took place 3 days per week compared to 2 days per week, 0.34 cm versus 0/29 cm respectively.

Discussion

The current research suggests BFR with low load exercise training is effective improving muscle strength and size. This was true for both aerobic and resistance training. When performing BFR aerobic exercise, training durations >6 weeks produced greater strength increases, which is the generally accepted adaption period for standard resistance training. Greater strength gains with BFR resistance training may be expected at an intensity >20% 1 RM.

Conclusion

This systematic review provides evidence of greater increases in muscle size and strength when exercise is combined with BFR, compared to low load exercise alone. This type of training offers potential benefits for populations recovering from orthopedic or other conditions that require rehabilitative care, for which higher load training is contraindicated. However, this study reveals there is a gap in the evidence in regards to optimal training methods and protocols, which would be important for future research.

Practical PTF Take-Aways

1. Lighter load BFR Training may be effective to increase muscle size and strength when traditional high load training in contraindicated
2. Adaptations and benefits are greater at 30% 1 RM compared to 20% 1 RM
3. Training durations >6 weeks offer greater returns in strength adaptions
4. BFR training can be applied to a range of populations who seek to progress strength while reducing loads on associated muscle, connective, tendinous, and bony tissues

Reference

Slysz. J, Stultz, J., Burr, J (2016). The efficacy of blood flow restricted exercise: A systematic review & meta-analysis. Journal of Science and Medicine in Sport. 19: 669-675.

Introduction

Lateral ankle sprains are one of the most common injuries for physically active individuals, occurring when the ankle rolls or gives out during activity. An ankle sprain can involve tearing of some or much of the ligament fibers of the ankle. Chronic Ankle Instability (CAI) happens when the ankle is repeatedly sprained, occurring around 30-40% of the time. One theory behind the prevalence of CAI is the change in balance and position receptors input and output, altering the ankle’s neuromuscular control. This study examined if balance training on the stable ankle would have any effect on the unstable ankle.

Methods

27 individuals between the age 13-35 volunteered for this study; 13 were in the treatment group, and 14 were in the control group. Both groups participated in pre-training and post-training testing, which consisted of an ankle and foot outcome measure, a dynamic balance test of both legs, and a static balance test of both legs.

Treatment

The treatment group participated in a 30-minute physical therapy session twice per week for four weeks. Each individual’s program consisted of the same 8 balance activities, which were modified and progressed in difficulty as appropriate by a Physical Therapist. Activities included: single leg standing on different surfaces, single leg hopping in different directions, tossing and catching a ball while on one leg, and hip hikes. The individuals were training their stable ankle only; if their left ankle had CAI, all of these activities were performed on their right ankle. The control group were instructed to continue their normal activities, and to not work on any ankle or balance specific exercises.

Results and PTF Implications

Following the 4 weeks of balance training on the stable ankle, the rehabilitation group showed statistically significant improvements in all three testing measures compared to the control group, including static and dynamic balance. This study showed that training the stable ankle increased the neuromuscular control of the unstable ankle, which in turn could decrease the risk of future ankle sprains. Here at Physical Therapy First, we will use this information to help an individual who may be experiencing CAI and balance limitations. We can apply the results of this study to improve your balance and stability in your affected ankle using both lower extremities. Our licensed Physical Therapists have the knowledge and expertise to get you safely back on both feet, even if that means training only one foot at a time.

Reference

Hale SA, Fergus A, Axmacher R, Kiser K. Bilateral improvements in lower extremity function after unilateral balance training in individuals with chronic ankle instability. Journal of Athletic Training. Volume 49, Number 2, pages 181-191.

Introduction

For athletes, post-exercise cold therapy is a widely accepted recovery modality to decrease muscle soreness and muscle swelling, and facilitate a speedier recovery. Cold-water immersion (CWI) and partial-body cryotherapy (PBC) are two forms of cold therapy intended to improve muscle recovery in athletes. The authors in the study, Cold-water or partial-body cryotherapy? Comparison of physiological responses and recovery following muscle damage, compare physiological markers including muscle oxygen saturation (SmO2), cutaneous vascular conductance (CVC), mean arterial pressure (MAP), and skin temperature in participants following CWI or PBC to compare the effectiveness of both modalities.

 Materials and Methods

Twenty male participants regularly involved in moderate physical endurance exercise volunteered for the study. The experiment followed a parallel group design and the participants were randomly assigned to either the CWI or PBC group. Both groups performed a muscle-damaging exercise which included five sets of 20 box jumps. Following the exercise, the participants received either CWI or PBC. The CWI involved immersing in cold water (+10 degrees Celsius) up to sternum level for ten minutes. The PBC participants entered a cryocabin  for two and a half minutes (-60 degrees Celsius for 30 seconds and -135 degrees Celsius for two minutes).

Physiological parameters which include SmO2, CVC, MAP, and skin temperature were measured before and immediately following exercise as well as in ten-minute intervals up to 60 minutes post-exercise. Indirect markers of muscle damage including rating of delayed onset of muscle soreness (DOMS), anterior thigh muscle swelling, 2-leg vertical jump performance (VJP), and maximal voluntary contraction (MVC) of the knee extensors, were assessed pre-exercise and 24, 48, and 72 hours post-exercise.

Results

Physiological Parameters

SmO2: There was a greater reduction in SmO2 following CWI compared to PBC at ten minutes and 40     minutes after exposure.

CVC: CWI decreased CVC significantly 10 minutes after the treatment compared to baseline values.

MAP: A significant increase was observed in both groups only directly after the treatments compared to baseline.

Mean Skin Temperature: The mean skin temperature was significantly lower in the PBC group only immediately after the treatment compared to the CWI group. Ten minutes following treatment, the CWI group had significantly lower temperature than the PBC group.

Recovery Parameters

Anterior Muscle Swelling: Compared to baseline, swelling was significantly increased in only the CWI group.

VJP: The CWI group had lower performances at 60 minutes after the treatment compared to baseline values.

MVC: MVC significantly decreased compared to baseline values at 60 minutes post-treatment in both groups. Both groups recovered their MVC within 24 hours.

DOMS: DOMS peaked at 24 hours in the PBC group and after 48 hours in the CWI group compared to baseline. Neither the PBC group nor the CWI group recovered from DOMS 72 hours after the damaging protocol and there was no significant difference for DOMS between groups.

Conclusions

The primary findings of the study are that the physiological impact of CWI was significantly greater than PBC. There was decreased oxygen saturation, decreased vascular conductance, increased arterial pressure, and reduced skin temperature in the CWI group as compared to the PBC group. This restriction of blood flow to the muscle helps to wash out waste products like lactic acid which cause muscle soreness, decrease metabolic activity, and reduce swelling and tissue breakdown.

There was no differences in objective and subjective recovery between CWI and PBC up to 72 hours post-exercise. This is the first study to compare the physiological responses and muscle recovery effects between CWI and PBC. The results suggest that either modality could be used for muscle recovery after exercise. The largest limitation in this study is the lack of a control group. It is important that additional studies include a control group to compare these two interventions to passive recovery.

PT First Implications

Cryotherapy in the form of CWI or PBC could be effective in promoting quicker, less painful muscle recovery after exercise. PT First’s therapists are capable of evaluating and screening athletes for exercise induced injuries and recommending various forms of cryotherapy treatment as an adjunct to skilled physical therapy.

Reference

Hohenauer, E., Costello, J., Stoop, R., Kung, U., Deliens, T., Clijsen, R (2017). Cold‐water or partial‐body cryotherapy? Comparison of physiological responses and recovery following muscle damage. Scandinavian Journal of Medicine &Science in Sports. Volume 28, Issue 3.