Table 3.

Studies about the effect of the shoe on pressure distribution.

Authors	Year of publish	Subjects	Shoe's type	Activity	Result	Methodology
Schaff and Cavanagh [100]	1990	8 males	1- Simple extra-depth shoe 2- Shoe with a 24° rocker bottom design.	Gait (walking)	Rocker-bottom shoes demonstrated a 30 % decrease in peak pressures within the medial and central forefoot and toe regions while showing an increase in pressures in the heel, midfoot, and lateral forefoot areas compared to simple shoes.	A pressure-measuring insole with 72 active elements was used in the right shoe for detailed calibration and measurements.
Jordan and Bartlett [83]	1995	15 males	3 casual shoes	Gait (walking)	Higher total plantar force and force-time integral were associated with decreased perceived comfort. Additionally, decreased comfort on the upper part of the shoe was connected to lower dorsal forces and pressures. However, there was no significant correlation between comfort and overall peak plantar pressure, pressure-time integral, or total plantar area.	A survey was utilized to assess comfort perception. Furthermore, upper foot pressure distribution was measured using a rectangular sensor pad set at 30 Hz, whereas the Mikro-EMED insole, operating at 100 Hz, was employed to measure sole pressure distribution.
Eils et al. [101]	2004	21 males	Soccer shoe	4 soccer-specific movements (normal run (gait), cutting maneuver, sprint, and goal shot)	Increased pressure values were noted during cutting (medial part of the foot), sprinting (first and second ray), and kicking (lateral part of the foot) in contrast to a normal run. However, no notable overall impact of varying surfaces on pressure parameters was observed.	The collection of plantar pressure distribution during movements was conducted using the Pedar Mobile system. This system comprised flexible insoles embedded with 99 sensors, offering a sampling frequency of 50 Hz.
Stewart et al. [102]	2007	6 females and 4 males	1- Flat training shoes 2- MBT shoe	Gait (walking)	MBT shoes demonstrated a 21 % pressure reduction under the midfoot and an 11 % decrease under the heel. However, they showed a 76 % increase in pressure under the toes, resulting in a shift of pressure towards the front of the foot.	A Pedar Ltd. in-shoe system from the UK was utilized to measure both mean and peak pressures in foot areas, in addition to determining the total sole contact area.
Owings et al. [103]	2008	11 females and 11 males	Barefoot and with 3 distinct insoles in a flexible and rocker-bottom shoe.	Gait (walking)	The shape and pressure-based insole used in the flexible shoe showed superior performance in 64 out of 70 regions compared to shape-based insoles. It decreased both peak pressure and force-time integral; however, it led to an increase in force-time integral specifically at the midfoot.	Plantar pressure was measured during barefoot walking using an emed-D pressure platform and by acquiring foam impressions of the feet. Furthermore, in-shoe plantar pressures were recorded using pressure-sensitive arrays from the Pedar-X system under different footwear conditions.
Hagen and Hennig [82]	2009	20 males	NIKE Air Pegasus shoes with different numbers of eyelets (ranging from 1 to 7 pairs) and the tightness of the laces (weak, regular, or tight).	Gait (Running)	Various lacing conditions showed different effects: the seven-eyelet pattern lowered peak pressures under the heel and lateral midfoot, and regular six-eyelet cross-lacing increased loading rates and peak pressures under the heel. perceived comfort remained consistent across lacing patterns, and low lace shoe conditions resulted in reduced impacts and peak pressures under metatarsal heads III and V.	The ground reaction forces, in-shoe pressure distribution, tibial acceleration, and rearfoot motion during running were measured using a piezoelectric force platform from Kistler, piezoceramic transducers from Halm, an Entran accelerometer, and a goniometer with a potentiometer from Megatron.
Hagen et al. [81]	2010	14 males	NIKE Air Pegasus with four lacing patterns (one regular, one tight, and two seven-eyelet lacings (A57, ALL)).	Gait (running)	Subjects perceived the tightest six-eyelet lacing (TIGHT6) and the seven-eyelet lacings (A57, ALL) as the most stable, with A57 being the most comfortable. Peak dorsal pressures were highest with TIGHT6, but the seventh eyelet in A57 and ALL notably reduced pressures on the tarsal bones, aligning with perceived stability and comfort.	Dorsal foot pressures were recorded using a Pedar Insole from Novel GMBH (Munich, Germany). Sensor and eyelet locations were identified through qualitative methods and MRI scans. Evaluation of dorsal pressures in eight anatomical regions was performed utilizing 54 activated sensors embedded in the Pedar sole.
Fiedler et al. [104]	2011	16 females and 4 males	3 shoes with different lacing tightness: 1- Comfortable 2- Loosened 3- Completely loose	Gait (walking)	Alterations in lace tightness resulted in notable pressure adjustments in the hallux, toes 2–5, and the lateral midfoot; however, there was no considerable impact observed on peak or average pressure. Participants noted heightened heel slippage and increased foot mobility when the laces were loosened.	Plantar pressures were measured utilizing the Pedar1-X in-shoe system, while perceived in-shoe displacement was evaluated utilizing a numerical rating scale.
Hillstrom et al. [29]	2013	25 early walkers	1- Barefoot 2- UltraFlex 3- MedFlex 4- LowFlex 5- Stiff	Gait (walking)	The Stiff shoe demonstrated the least peak pressures, whereas the UltraFlex shoe exhibited the highest peak plantar pressures. Additionally, in numerous regions of the plantar foot, the pressures from the UltraFlex shoe closely resembled those experienced during barefoot loading, making them indistinguishable in most areas.	The emed-x system employed capacitance-based force transducers and a 12-region anatomical masking algorithm to measure barefoot plantar pressures. Conversely, the Pedar-X system gathered in-shoe plantar pressures using capacitance-based transducers across various shoes.
Stewart et al. [105]	2014	3 females and 33 males	1- Footwear owned by participants. 2- research footwear chosen by participants, including: a) 21 shoes with good characteristics. b) 15 shoes with poor characteristics.	Gait (walking)	When compared to the shoes owned by participants, shoes with favorable attributes demonstrated a decrease in peak pressure at metatarsals 3 and 5, but concurrently led to heightened pressure time integrals in the midfoot. In contrast, shoes with unfavorable characteristics amplified peak pressure beneath the heel and lesser toes, while diminishing pressure time integrals in the midfoot.	Plantar pressure readings were obtained using the F-Scan Mobile system, which comprises insoles containing 960 pressure-sensing locations. Data collection involved a five-stride protocol, and analysis was performed using the F-Scan software. Spatial and temporal parameters of gait were measured utilizing the GAITMAT II TM, which incorporates six sensor arrays.
Lam et al. [106]	2017	20 males	Footwear featuring midsoles with varying hardness levels (60 and 50 Shore C).	Running (gait), maximal forward sprinting, maximal 45° cutting and lay-up	Lower peak pressure and pressure-time integral across multiple plantar regions during various activities were observed in soft shoes when compared to hard shoes.	The measurement of plantar pressure distribution was conducted using the Pedar Mobile System, which features 99 sensors. Additionally, the capture of shoe-ground angles at touchdown was accomplished through a high-speed camera, while speed measurement during the running task was facilitated by infrared timing gates.