Syfte Syftet med studien var att undersöka om sprint- och uthållighetsförmåga vid löpning samt relativ arbetsintensitet under fotbollsmatch, enskilt eller tillsammans, har ett samband med löpdistans i olika intensitetszoner under fotbollsmatch för elitflickfotbollsspelare. Metod Studiens datainsamling delades upp i två delar, första delen syftade till att bestämma individernas sprint- och uthållighetsförmåga utifrån ett 30 m sprinttest och ett Beep-test. Under Beep-testet bestämdes individernas maximala hjärtfrekvens (HFmax) samt antal genomförda 20 m-sträckor, vilka låg till grund för beräkning av den maximala syreupptagningsförmågan (V̇O2max). Den andra delen av datainsamlingen gjordes under en fotbollsmatch, där den relativa arbetsintensiteten i form av medelhjärtfrekvensen (HFmed) registrerades. Under matchen analyserades spelarnas löpdistans i olika hastighetszoner, 0-11 kmtim-1 (LDlåg); 11-21 kmtim-1 (LDmod); > 21 kmtim-1 (LDhög), genom användning av ett videobaserat analysprogram. Resultat Det fanns ett signifikant samband mellan individernas HFmed och LDmod (r = 0,81; p = 0,049). För att öka förklaringsgraden av LDmod gjordes en multipel linjär regression där HFmed användes som utgångsvariabel och kombinerades med V̇O2max. HFmed och V̇O2max bidrog signifikant till prediktionsmodellen och modellen förklarade 93,9% av variationen i LDmod. Slutsatser Genom fastställandet av en elitflickfotbollsspelares uthållighetsförmåga samt dennes relativa arbetsintensitet under match, så kan spelarens löpdistans i hastighetsintervallet 11-21 kmtim-1 förutsägas med god precision utan att kostsam analysutrustning behöver användas.

Monitoring progress of athletes is an essential component of the training process. Collegiate distance running coaches often use field tests to assess progress because of a lack of time and resources to do laboratory testing. The purpose of this dissertation was to examine the relationships between physiological and strength variables measured in a laboratory and field testing measures in collegiate distance runners. Collegiate distance runners completed a series of tests in the Sport Science laboratory at East Tennessee State University to obtain physiological and strength parameters, such as V̇ O2max and vertical jump height. The athletes then completed one of two field tests (either a 3 km time trial or a 3 minute all out run test). There were strong correlations between the laboratory measures and the field test performances. These results indicate that strength is an important factor in run performance. Also, a 3 km time trial and a 3 minute all out run test are suitable for athlete monitoring.

At any given running speed, weight support with a lower body positive pressure (LBPP) device (i.e. Alter-G treadmill) reduces V̇O2. However, it is unknown how application of LBPP during running impacts lactate metabolism, specifically lactate threshold. Purpose: To determine if body weight unloading with the Alter-G treadmill alters lactate threshold. Methods. Maximal aerobic capacity (V̇O2max) and lactate threshold (LT) was determined in 8 male subjects on an Alter-G treadmill at 100% and 80% body weight loading at 0% grade in a randomized crossover design. V̇O2max tests started at 7 mile h-1 and increase speed by 1 mile h-1 every 2 min till voluntary exhaustion and were separated by a minimum of 7 days. LT tests started at 5 mile h-1 and increased speed to 6, 7, 7.5, 8.0, 8.5, 9.0 (additional stages increase speed by 0.5 mile h-1) every 3 min until the subject reached ¡Ö85% of V̇O2max. LT tests were separated by a minimum 3 days. V̇O2, heart rate (HR), mean arterial blood pressure (MAP) and changes in Hct, [Hb], and total protein ([TP]) were determined on separate days in a randomized crossover design. Plasma lactate concentrations were determined from venous blood samples (4 ml) obtained at rest and during the last minute of each exercise stage. Lactate threshold was determined from a log-log plot of lactate concentration (mM) and relative V̇O2 (ml O2 min-1 kg-1 BM). Results. V̇O2max determined during running at 100% and 80% loading were similar (52.3 ± 0.9 and 52.7 ± 0.7 ml O2 min-1 kg-1 BM, respectively). The energy cost of running at 9 mile h-1 (all subjects completed stages between 5 and 9 mile h-1) was reduced by 12% at 80% body weight (37.2 ± 2.9 ml O2 min-1 kg-1 BM) compared to running at 100% body weight (42.3 ± 1.7 ml O2 min-1 kg-1 BM, <0.05). However, plasma lactate at 9 mile h-1 was similar during 80% and 100% body weight running (3.4 ± 0.4 and 3.1 ± 0.7 mM, respectively). Plasma lactate at a given V̇O2 was higher (p < 0.05) while running at 80% body weight compared to 100% body weight running. Calculated LT at 100% BW loading (36.3 ± 1.3 ml O2 min-1 kg-1 BM) was higher than 80% BW loading (32.2 ± 1.8 ml O2 min-1 kg-1 BM, p<0.05). During running at 80% BW HR was reduced compared to 100% BW running (p<0.05) however the MAP response was similar. During exercise the reduction in PV, at any given V̇O2 was larger at 80% BW compared to 100% BW running (p<0.001). Conclusion. During running, BW unloading with LBPP decreased the energy cost of exercise but not lactate levels. Body weight unloading caused a lowering of the LT. The reduction in whole body energy cost was not associated with a reduction in the lactate production since plasma lactate accumulation at a given speed was similar with and without LBPP.