Abstract des Autors

Only few conclusive studies about training-induced adaptations within the arterial vascular system in humans have been published so far. Therefore, we investigated the central and peripheral arteries in non-disabled and disabled athletes, who showed different functional properties of the upper and lower limb musculature caused by training or a physical handicap. In untrained and highly trained non-disabled subjects (32 untrained students (UT), 18 tennis players (TP)), in sedentary (UPP, N=16) and wheelchair-trained paraplegics (TPP, N=26) and in trained amputees (arm amputees (A-AM), N=11; leg amputees (L-AM), N=17) elastic type (aorta) and muscular type limb arteries were analysed by duplex sonography. Diastolic diameter (D) of subclavian (Sub), brachial (Bra), femoral (Fem) and popliteal (Pop) arteries as well as the thoracic (AOT) and abdominal aorta (AOA) were determined using 3.5/5 MHz sector probes. Cross-sectional areas (CSA) were calculated (CSA = 3.14 x (D/2)**2) and set in relation to body surface area (BSA) (CSA/BSA). Regional blood flow (BF/MIN) was measured with a pulsed Doppler and set in relation to heart rate (BF/HR). Diastolic diameter (30-40%) and QSA/BSA (50-70%) of Fem and Pop were significantly decreased in UPP and TPP compared to UT. The arteries proximal the lesion of the injured limb in A-AM and L-AM showed a similar reduction of D and QSA/CSA. TPP demonstrated significantly increased diastolic diameter (15-25%) and CSA/BSA (30-50%) of Sub compared to UPP and UT. Diastolic diameter (20%) and CSA/BSA (40%) of Sub and Bra of the playing arm in TP were significantly elevated compared to the opposite side. Similar changes of D and CSA/BSA of the extremity arteries were found at the intact limbs in A-AM and L-AM. AOT and AOA showed no significant dimensional changes in all groups. Dimensional changes in Sub and Fem were associated with corresponding alterations in BF/HR. Regular training of the upper limb musculature is associated with an increase of the dimensions of Sub and Bra at the playing arm in tennis players and both arms in paraplegics. Traumatic extremity loss in amputees or paralysis of the lower limb musculature in paraplegics are connected with a reduction of the dimensions of the supplying arm (SUB, BRA) or leg (FEM, POP) arteries. The dimensional changes are associated with a concomitant increase or decrease of regional blood flow. The results indicated structural and functional adaptations of muscular type extremity arteries dependent on the metabolic demands of the extremity musculature. Verf.-Referat