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Venous return for those who study the performance is an important aspect
The internal load and recovery are affected by venous return
circulatory pressure and cardiac output (the volume of blood ejected per minute) are affected
Skin microcirculation and the elimination of toxins are affected
The lymphatic return is connected to it
Physiol Rev. 2008 Jul;88(3):1009-86. doi: 10.1152/physrev.00045.2006. Regulation of coronary blood flow during exercise. Duncker DJ1, Bache RJ.
The factors regulating the venous return are known, valves, venous squeezing, pressure gradient, etc. favoring the return of blood to the heart. In particular for athletes are relevant the pressure gradient ( the pressure between the contact areas to the ground and the heart) this must remain in favor of the contact areas, the greater is this easer will be the return of the blood to the heart. For a sitting sport this becomes more important to those who practice.
In sports muscle contractions are equally important. There is a profound difference in the sport with ceilings and explosive contractions, such us weight lifting, football etc where the venous return results often more complex because of the amount of muscle compression. (Static defined in the technical language) Compared to sports considered by dynamic technical language where more modular contractions but compressive facilitate venous passage, like cycling. Both situations still require aid venous return.
Il ruolo rilevante del piede
The arches of the foot form a vault that favor the yielding of the same with a consequent increase of pressure at this level, it is clear that the movement amplifies this effect.
The capillary bed present in the breech vault suggests that there is an important venous stasis and now many argue that the venous return starts from his foot.
Anat Rec (Hoboken). 2010 Mar;293(3):370-8. doi: 10.1002/ar.21085. The anatomy and physiology of the venous foot pump. Corley GJ1, Broderick BJ, Nestor SM, Breen PP, Grace PA, Quondamatteo F, Olaighin G.
Dermatol Surg. 2014 Mar;40(3):225-33. doi: 10.1111/dsu.12381. Epub 2013 Dec 23. The foot venous system: anatomy, physiology and relevance to clinical practice. Ricci S1, Moro L, Antonelli Incalzi R. Abstract OBJECTIVE: This review aims to summarize present knowledge of foot venous return, with a special interest in clinical and research implications. METHODS: It is based on the latest available publications on foot anatomy and hemodynamics. MATERIALS ANATOMY: Five systems are described: the superficial veins of the sole, the deep veins of the sole (with particular attention to the lateral plantar vein), the superficial dorsal plexus, the marginal veins and the dorsal arch and the perforating system. The Foot Pump: The physiology of venous return is briefly described, with an emphasis on the differences between standing and walking and the interplay of the foot and calf venous systems. RESULTS: The hypothesis that the foot and calf venous systems may be in conflict in several clinical conditions (localization of leg ulcers, corona phlebectatica, foot vein dilatation, arteriovenous fistulas of the foot, foot-free bandaging) is presented, briefly discussed, and mechanistically interpreted. CONCLUSIONS: Foot venous return could be more important than is commonly thought. Certain clinical conditions could be explained by a conflict between the mechanisms of the foot pump and the leg pumps most proximal to the foot, rather than by generic pump insufficiency, with possible effects on treatment and compression strategies.
Why define venous heart? Obviously because from this point part of the venous return
J Vasc Surg. 1996 Nov;24(5):819-24. Venous outflow of the leg: anatomy and physiologic mechanism of the plantar venous plexus. White JV1, Katz ML, Cisek P, Kreithen J.
Phlebology. 2015 Apr;30(3):180-93. doi: 10.1177/0268355513517686. Epub 2014 Jan 10. Anatomy of the veno-muscular pumps of the lower limb. Uhl JF1, Gillot C2. Author information Abstract OBJECTIVE: To study the anatomy of the veno-muscular pumps of the lower limb, particularly the calf pump, the most powerful of the lower limb, and to confirm its crucial importance in venous return.
RESULTS: The foot pump is the starter of the venous return. The calf pump can be divided into two anatomical parts: the leg pump located in the veins of the soleus muscle and the popliteal pump ending in the popliteal vein with the unique above-knee collector of the medial gastrocnemial veins. At the leg level, the lateral veins of the soleus are the bigger ones. They drain vertically into the fibular veins. The medial veins of the soleus, smaller, join the posterior tibial veins horizontally. At the popliteal level, medial gastrocnemial veins are the largest veins, which end uniquely as a large collector into the popliteal vein above the knee joint. This explains the power of the gastrocnemial pump: during walking, the high speed of the blood ejection during each muscular systole acts like a nozzle creating a powerful jet into the popliteal vein. This also explains the aspiration (Venturi) effect on the deep veins below. Finally, the thigh pump of the semimembranosus muscles pushes the blood of the deep femoral vein together with the quadriceps veins into the common femoral vein.
CONCLUSION: The veno-muscular pumps of the lower limb create a chain of events by their successive activation during walking. They play the role of a peripheral heart, which combined with venous valves serve to avoid gravitational reflux during muscular diastole. A stiffness of the ankle or/and the dispersion of the collectors inside the gastrocnemius could impair this powerful pump and so worsen venous return, causing development of severe chronic venous insufficiency.
The postures with different pressures
It becomes really important to help those in need to the position or the posture to have a good venous return
Although Im doubtful on the values shown in this image, this highlights the critical nature of those who were sitting
A useful aid to the improvement of venous return encompasses many benefits in athletes: Improvement in cardiac
output Less time in the disposal of
toxins Tissue oxygenation
improvement Increased metabolic potential
of the subject
The environment affects greatly on the venous return, flooring, postures and footwear often cause bad blood flows back to the heart
It appears evident that in this example level differences between forefoot and rear foot downloading in a different way the plantar arch and activated in a negative way the movement of the ankle, articulation important for the venous return.
The gravity, the body center of gravity destabilizing elements but also primary elements, to consider, in the search of bodily equilibrium.
Obviously improper or unbalanced postures tend to weigh more on some muscle chains and to close essential joint angles for the passage of the venous flow, example is the closure of the knee angle in sitting posture.
In these three images I have described the forces at play in the impact of the foot with the ground, study them is essential to overcome traumas to the athlete's load.
The athlete who pushed generate much higher forces coming to two to three times its weight. A high-performance surface must return and absorb the forces in favor of the performance
The forces to the ground, at the stage immediately after that of the sprint, are amplified up to 5 times the maximum speed to the athlete's weight.? This phenomenon is more evident in the race existing in the biomechanics of the gesture a flight phase and supports generally monopodalic
With baropodometric instrumentation through the study of the pressures ,can be analyzed force and pressure at the arch level so understanding what are the sports that are most in need of assistive acts to help the venous return. In addition the individual athlete understand the type of support breech.
or example in a subject walking of approximately 60 kg of weight we can detect forces to the maximum average double foot to its mass, with average forces representing almost half of the same. Dependent on the speed of the gesture. Recall that in the physical force is; mass X acceleration
In cycling instead the forces are nearly equal to the body weight of the subject with medium that are a third of the weight of the subject itself. It is obvious that the venous return is complicated. The pressure increase instead, this for the reduced space on which to spread the force (metatarsal heads). Recall that the pressure is, Strength / space (surface) in physics on which it is developed
Int J Sports Med. 1996 Jan;17(1):17-21. Cycling cadence alters exercise hemodynamics. Gotshall RW1, Bauer TA, Fahrner SL. Author information Abstract Previous studies on cycling cadence have focused on the economy of the cadence, in search of the optimal pedal cadence. The purpose of this study was to determine the hemodynamic changes associated with varying pedal cadence at a constant workload. It was hypothesized that increased pedal cadence would enhance the skeletal muscle pump, resulting in elevation of cardiac output. Seven cyclists were enlisted to cycle at 200 watts at pedal cadences of 70, 90 and 110 rpm (random order). Oxygen uptake, heart rate, stroke volume, cardiac output, blood pressure, and vascular resistance were determined. As has been previously shown, oxygen uptake increased with increased cadence (70, 90, 110 rpm) at this workload. Heart rate, stro