Thesis advisor: Christopher Maxwell / Nike claims that their shoes, the Nike Vaporfly 4%'s, will make you 4% faster in your next marathon. This claim is evaluated by way of econometric analysis of large scale, publicly sourced data. This study seeks to prove whether or not Nike's claim is valid, and assess the implications of such technology in both competitive and amateur running. / Thesis (BA) — Boston College, 2021. / Submitted to: Boston College. College of Arts and Sciences. / Discipline: Departmental Honors. / Discipline: Economics.

Our purpose was to evaluate effects of cadence manipulation on plantar loading during running. Participants (n=38) ran on a treadmill at their preferred speed in 3 conditions: preferred, 5% increased, and 5% decreased while measured using in-shoe sensors. Data (contact time [CT], peak force [PF], force time integral [FTI], pressure time integral [PTI] and peak pressure [PP]) were recorded for 30 right footfalls. Multivariate analysis was performed to detect differences in loading between cadences in the total foot and 4 plantar regions. Differences in plantar loading occurred between cadence conditions. Total foot CT and PF were lower with a faster cadence, but no total foot PP differences were observed. Faster cadence reduced CT, pressure and force variables in both the heel and metatarsal regions. Increasing cadence did not elevate metatarsal loads; rather, total foot and all regions were reduced when healthy runners increased their cadence. If a 5% increase in cadence from preferred were maintained over each mile run the impulse at the heel would be reduced by an estimated 565 body weightss (BWs) and the metatarsals 140-170 BWs per mile run despite the increased steps taken. Increasing cadence may benefit overuse injuries associated with elevated plantar loading.

OBJECTIVES:: Evaluate effects of a new off-the-shelf insert on frontal plane foot biomechanics and compare effectiveness of the new and an existing off-the-shelf insert and a motion-control shoe in neutralizing frontal plane foot biomechanics. Design: Descriptive. Setting: Biomechanics laboratory. Participants: Fifteen uninjured subjects with a flexible flatfoot secondary to forefoot varus. Assessment of risk factors: Three-dimensional kinematic and kinetic data were collected as subjects walked and jogged at their self-selected speed while wearing a motion-control running shoe, the shoe with a new off-the-shelf insert, and the shoe with an existing off-the-shelf insert. Main outcome measures: Frontal plane kinematics and rearfoot kinetics were evaluated during stance. Statistical analysis was performed using a repeated measures analysis of variance and Student-Newman-Keuls post hoc tests (α ≤ 0.05). Results: The new insert and motion-control shoe placed the forefoot in a less-everted position than the existing off-the-shelf insert during walking. There were no differences in forefoot kinematics during jogging, nor were there differences in rearfoot motion during walking or jogging. The rearfoot eversion moment was significantly lower with the new off-the-shelf insert compared with the motion-control shoe and the existing insert during walking and jogging. Conclusions: A new off-the-shelf device is available that promotes more neutral frontal plane biomechanics, thus providing a theoretical rationale for using this device for injury prevention and treatment. The comparative biomechanical effectiveness of a motion-control shoe and the orthotic inserts may assist health care professionals in selecting a device to correct the flatfoot structure.

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For years track and field athletes have worn spiked shoes to enhance performance. This study was conducted to determine the effect of track spikes on hip, knee, and ankle peak joint moments (PJM) in collegiate and elite athletes while running. To measure differences in joint moments, ten intercollegiate and post graduate male distance runners from Brigham Young University ran at a four-minute-mile pace (6.7 m/s) across a force plate synched with infrared cameras tracking body positioning in each shoe condition. Repeated measures ANOVA (p < 0.05) revealed no significant peak joint differences between running shoes and track spikes. The minimum hip and peak knee PJM approached significance (F = 3.221, P = 0.116 and F = 2.875, P = 0.134 respectively). The high variability of joint moments between trials made it difficult to detect differences between conditions. The variability may be explained by any number of factors including: biomechanical differences in running form, running at high speeds, type of subjects, and potentially other factors.

In the sport of track and field, runners excel at their events due not only to physiological characteristics but aspects in their form. Characteristics in form help runners achieve the goal in completing their event in the least amount of time possible. For sprinters, this is done by having a shorter swing phase and ground time along with greater power and a longer stride length. Distance runners accomplish the goal of quicker speeds by balancing it with running economy by spending greater time on the ground with shorter stride lengths compared to those in shorter distance running events. Middle distance runners must find a balance between power and running economy for greater success in the 800 meter and 1600 meter runs. If these characteristics are true for runners while competing in their event, would they also be seen at speeds slower and faster than what they compete at? Purpose: This study was conducted to determine if sprinters, middle distance runners, and distance runners running at the same speeds would exhibit different characteristics in their form which aid them in their events. Methods: Thirty female Division I collegiate runners participated in this study. Runners were separated into categories based on the events they were currently training in: 10 sprinters, 10 middle distance runners, and 10 distance runners. All participants were asked to run for twenty two steps at 3.17 m/s (8:27 min/mile), 3.58 m/s (7:30 min/mile), 4.11 m/s (6.31 min/mile), 4.87 m/s (5:30 min/mile), and 5.95 m/s (4:30 min/mile) pace. Motion analysis was captured at each speed recording knee angles, ground time, center of mass separation, and stride length at 240 Hz. Data was then processed using ANOVA and a Tukey post hoc analysis. Results: Significant differences (p < .05) occurred between distance runners and the groups of middle distance runners and sprinters in knee range, ground time, center of mass separation, and stride length while running at the same speed for all of the five speeds. All groups displayed similar liner slopes as speeds increased with no interactions occurring between groups. As the speed increased, all three groups decreased in knee range measurements and ground time measurements. Increases in speed displayed and increase in center of mass separation and stride length among all three groups. Conclusion: While running at the same speeds, runners exhibit specific characteristics in their form that benefit them in their event. These are even seen in speeds that are faster or slower that what the athletes are used to training at or competing at. In addition, middle distance runners display aspects of form that are between distance runners and sprinters in all variables. By understanding these differences, coaches and athletes can analyze current performance and make needed adjustments.

Introduction. Exercise and head-out water immersion (HOI) have consistently reported an increase in central blood volume associated with the cephalad shift in blood volume. This causes an increase in left ventricular end diastolic volume and greater stroke volume during exercise compared to exercise in air at similar metabolic costs. In contrast, the metabolic response, specifically, blood lactate accumulation during exercise combined with HOI has yielded varying results depending on the mode of exercise. At present it appears that during exercise at similar metabolic costs, cycle ergometry exercise augments plasma lactate over treadmill running while HOI reduces the plasma lactate response to cycle ergometry exercise. The interaction between treadmill running and HOI appears less certain. Thus, we tested the hypothesis that running on a treadmill on land would result in a lesser accumulation of lactate than during HOI treadmill running. Methods. Eleven subjects' lactate thresholds were determined while running at a 0% grade at increasing speeds on a treadmill on land or during HOI on an underwater treadmill in a randomized cross-over design. Exercise tests were separated by a minimum of 3 days. Lactate concentrations were expressed in mM• kg-1 H2O after correcting for plasma solid concentration. During exercise changes in plasma volume were calculated from changes in hematocrit and hemoglobin. Lactate threshold was estimated from a log-log plot of lactate concentration (mM• kg-1 H2O) as a function of relative oxygen consumption (ml O2•min-1•kg-1 BW). Results. The energy cost and heart rate response to running at speeds between 5.5 and 7.5 mph was similar for land and HOI. During treadmill running on land, plasma volume decreased by 6.4 ± 4.0% at a speed of 7.5 mph. The decrease in plasma volume was significantly greater during HOI and averaged 18.7 ± 1.7% (p <0.05) at 7.5 mph. Plasma lactate was higher at any given treadmill speed ≥ 5.5 mph during HOI compared to land (p <0.05). Lactate threshold during HOI running (21.8 ± 1.6 mM• kg-1 H2O) was lower (p <0.05) than during running on the land treadmill (27.0 ± 1.6 mM• kg-1 H2O). Discussion. HOI running resulted in a consistent shift to the left (rise in plasma lactate occurred at a lower ) in the lactate threshold and elevated plasma lactate concentration at speeds between 5.5-7.5 mph despite similar metabolic and HR responses to the exercise.

Sprinting on a curve is significantly slower than on a straightaway. Although the dimensions vary from track to track, indoor track curves are among the tightest curves that athletes will sprint at maximal speed. Previous studies have provided theories for how speed attenuation occurs when running on a curve. Yet, no previous research has determined how the variability of indoor track curve radii affects trained sprinters at maximal speeds. Purpose: To determine the differences in running speeds, ground time (GT), and medio-lateral (ML) impulse, with different indoor track radii. A secondary purpose was to understand the between-leg differences in GT and ML impulse during maximal sprinting on a curve. Methods: 10 male intercollegiate sprinters performed 45-m maximal sprints on a straightaway, 15-m track curve and 21-m track curve. A force platform embedded under an indoor track surface measured ground reaction forces while timing lights measured running speed. Analysis: A mixed models analysis of variance blocking on subjects was performed testing the main effects of the track curve on sprinting speed, GT and ML impulse (p<0.01). Results: Sprinting speed was significantly slower when running on a curve. GT increased for inside leg on both curved path conditions compared to straight. ML impulses increased as the radius of the track curve decreased. Discussion: If a 200m race were performed on both our track curves, the track with 21m curve would be 0.12s faster than the track with the 15m curve. GT and ML impulse results support leading explanations that the inside leg is the limiting factor during curve running. Tighter track curves require greater ML forces, but for a shorter period of time compared to larger track turns. Coaches and athletes should consider the radius of the track curve as they prepare for training and performance and consider injury risk. The speed differences observed due to the track curve radius may provide the first step to understanding how the radius of the indoor track curve affects sprinting speed and ultimately, performance.

Over the past century, the role of the vice presidency has increased drastically, to the point that some view the president and the vice president as a co-presidency. When this started and who perpetuated the change is up to debate, but the fact that the vice presidency and the vice-presidential selection process have increased in visibility and importance is not. This project analyzes the changes that occurred in the selection of the vice-presidential running mates in the last four decades by comparing the news coverage of the vice-presidential selection process in the years 1968 and 2000. What characteristics (such as ideology, compatibility, moral character, experience, etc.) do the media value most when reporting on the vice-presidential selection? The study observes the presidential election-year months of March through December in order to acquire data from the time the veepstakes speculation starts—after a presidential candidate secures enough delegates to win the nomination—to after the general election—where the electoral impact of the vice-presidential choice can be interpreted. / Master of Arts

Minimal footwear sales have encountered rapid growth over the last several years. Minimal footwear are often constructed with thin basic uppers and thin, flexible midsoles. It is likely that running in minimal footwear will require adaptation and adjustments as the amount of cushioning and the geometry of the foot/ground interface will be substantially different than what many are accustomed to. This research investigated the effect footwear cushioning amount and the running surface had on running patterns. Study 1 (Chapter IV) utilized two different running footwear conditions and two different cushioned treadmill conditions, as well as a barefoot condition, to investigate the effect cushioning magnitude and mode had on running patterns. Subjects ran for six minutes at 3.0 m/s for each footwear/surface condition while kinematics and acceleration data were collected. Study 2 (Chapter V) utilized three footwear conditions as well as a barefoot condition to investigate the effect of running in minimal footwear for the first time. Subjects ran for six minutes at 3.0 m/s while wearing each of the four conditions on an aluminum belt treadmill while kinematic and acceleration data were collected. The three footwear conditions were very similar except for the amount of underfoot material (foam) which varied from very little in the most minimal condition to a typical training footwear amount in the thickest condition. Study 3 (Chapter VI) utilized the same three footwear conditions worn in study 2. Subjects ran for 30 minutes at 3.0 m/s wearing each of the three footwear conditions while kinematic and acceleration data were collected in order to investigate the response to minimal footwear over the course of a sustained run. Results of Study 1 suggest that the amount of underfoot cushioning as well as how that cushioning was applied (footwear vs. surface) were both important and affected adjustments made during the run. The foot was more horizontal, the ankle joint complex more plantar flexed, and the knee more flexed in the sagittal plane at TD when running barefoot compared to all other conditions. Peak acceleration values were reduced for the most cushioned condition compared to all others. The thigh segment was more vertical at TD and peak tibial internal rotation at midstance was reduced when footwear were worn. This indicated cushioning provided through footwear altered running patterns compared to cushioning provided through the surface. More investigation is necessary to fully understand all the factors involved, but our research showed that cushioning magnitude is not the only factor affecting running patterns when footwear or running surface is altered. Some Study 2 dependent variables indicated running patterns to be significantly different for both barefoot and very minimal footwear conditions compared to footwear with thicknesses more similar to typical training footwear. Other dependent variables showed barefoot to separate from all footwear conditions implying that unique strategies were utilized for barefoot running even when compared to minimal footwear providing very little cushioning or protection. Peak accelerations implied that cushioning limited the shock transferred to the tibia and the head. Most coordination measures implied barefoot running to be significantly more variable than running in minimal running shoes. Adaptations due to running in footwear with unknown cushioning characteristics occurred quickly, in as few as six to eight steps. Kinematic adjustments were also occurring later in the six minute run. Study 3 kinematic and acceleration dependent variables indicated adjustments were made to running patterns as a result of changes in the amount of underfoot material. The foot segment was less horizontal and the AJC more dorsiflexed for the thick condition compared to both others. These changes did not completely compensate for changes in underfoot material however, as peak accelerations at the tibia and the head were increased as underfoot material was reduced. Runners were found to adjust running patterns as the thirty minute run progressed regardless of footwear condition. Several kinematic dependent variables were found to significantly increase or decrease as the 30 minute run progressed. In summary, the amount of cushioning and the mode of cushioning were found to effect running patterns. Given these findings, it is not surprising adaptations were found when comparing running in minimal footwear to running in footwear with more typical midsole thicknesses. Cushioning magnitude and the geometry of the foot/ground interface were substantially different between these footwear conditions. Although the thin condition provided almost no cushioning, differences were still shown between barefoot and this condition. Barefoot running may require a unique solution even compared to running in extremely minimal footwear. When runners wore minimal running shoes for the first time, some adaptations occurred quickly; however, adjustments were still occurring much later into the six and 30 minute runs. Runners who purchase minimal footwear can expect changes in running patterns.