The Use of Negative Pressure Wave Treatment in Athlete Recovery: 2134 Board #12 May 28, 5

Lower body negative pressure (LBNP) treatment, also known as intermittent vacuum therapy, was developed for astronauts, to maintain the arterial blood supply of the lower body and compensate for weightlessness. Due to the low gravity in space, autonomic cardiovascular control deteriorates and orthostatic tolerance is re-established by means of LBNP therapy after exploration flights. [1] Designed to act as an external heart for the lower body, the LBNP device generates a rhythmic alternating pressure of intermittent waves of negative pressure (lower pressure), and normal pressure (atmospheric pressure). As described in available literature this mechanism causes strong capillary dilation and compression pulsations[2] through which blood circulation and perfusion in the lower limbs are increased. [3] Arteries dilate as oxygen (O2)-rich blood and nutrients are drawn into the tissue (hypobaric), resulting in a higher available concentration of O2 and supplements in the muscle,[4] followed by an atmospheric pressure phase, a relief of the reflux, when carbon dioxide (CO2) and metabolic waste products are pressed back into the upper body through the circulatory system and the lymphatic vessels. [5] This application of sub-atmospheric pressure to the lower portion of the body (below the iliac crest) consequently enhances the baroreflex that assists in maintaining blood pressure during orthostatic stress. [1,2] In clinical applications, the use of negative pressure has been indicated as an effective modality. [4,6] A study by Schneider et al.[7] indicated an improvement in heart rate and blood pressure responses observed with the application of LBNP after 15 days of bed rest. Following excessive training, athletes often experience symptoms of discomfort, muscular soreness and stiffness within 12–24h, which can contribute to the development of muscular fatigue resulting in deteriorating performance. [8,9] Delayed onset muscle soreness (DOMS) is an inflammatory reaction caused by the micro-damage of primary muscle. Sports massage is a popular treatment and a frequently applied intervention; however, evidence to support its efficacy as a technique to enhance recovery is still being explored. [10] Appropriate methods of recovery are, however, essential to restore an athlete’s physiological and psychological capacities. Prompt and sufficient recovery can also improve performance by enhancing training quality and tolerance to the training load, as well as improving the athlete’s adaptation to training. Without proper recovery following multiple training sessions or competitions, an athlete increases the risk for poorer performance and overuse injuries. [8,10] Mimicking sports massage by stimulating the circulatory system and lymphatic vessels, LBNP is claimed to play a vital role in the recovery of the athlete in order to maximise athletic performance in competitive sport. The endurance capacity in athletes differs, with highly trained athletes performing at a higher maximal oxygen uptake, presenting with minimum lactate accumulation. During exercise of increasing intensity, an increase in blood lactate concentration is an indication of a rise in glycogen metabolism within the muscle. However, the initial increase in blood lactate concentration implies the net result of lactate production in the muscle, and reflects that the appearance rate of lactate in the blood is higher than the disappearance rate (the result of a balance between the rate of production and removal). [11,12] This is referred to as the lactate threshold and is Background: Athletes need to recover fully to maximise performance in competitive sport. Athletes who replenish more quickly and more efficiently are able to train harder and more intensely. Elite athletes subjectively report positive results using lower body negative pressure (LBNP) treatment as an alternate method for rapid recovery, restoring and improving their impaired physical state. Objective data on the efficacy are lacking. Objectives: To investigate the effect of intermittent vacuum therapy on accelerating acute recovery following an athlete’s normal daily training schedule of strenuous exercise. Objective measurements of biological markers of muscular fatigue were used to assess recovery. Methods: Twenty-two male cricket players in a randomised cross-over study were divided into a treatment and control group respectively. Following a one-hour high-intensity gym session, the treatment group received three 30-minute LBNP exposure sessions over three consecutive days (0, 24 and 48 hours). Blood lactate and creatine kinase biomarkers were collected to measure the recovery process. After 14 days groups were crossed over and the trial repeated. Results: Heart rate and blood pressure decreased noticeably during treatment, reverting to baseline levels after treatment. Lactate concentrations decreased in both groups after exercise termination; significantly more in the treatment (0.57±0.23 mmol/l) than control group (0.78±0.22 mmol/l), p<0.001). Creatine kinase (CK) was similar in both groups. Athletes’ subjective assessments of recovery rated moderately high. Conclusion: LBNP therapy applied as treatment during routine schedule may have a systemic effect in lowering serum lactate levels, but not CK levels. Enhanced recovery of athletes is still unconfirmed.