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P oposed P o ocol o Field Tes ing o Endu ance Fi ness o Young Lab ado Re ie e s
© 2023 by he au ho s. Licensee MDPI, Basel, Swi ze land
Published e sion
Söde lund, Ella-E ika; Ky öläinen, Heikki; Lai inen-Vapaa uo i, Ou i M.;
Hyy iäinen, Heli K.
Söde lund, E.-E., Ky öläinen, H., Lai inen-Vapaa uo i, O. M., & Hyy iäinen, H. K. (2023).
P oposed P o ocol o Field Tes ing o Endu ance Fi ness o Young Lab ado Re ie e s. Me hods
and P o ocols, 6(4), 61. h ps://doi.o g/10.3390/mps6040061
2023
Ci a ion: Söde lund, E.-E.;
Ky öläinen, H.; Lai inen-Vapaa uo i,
O.M.; Hyy iäinen, H.K. P oposed
P o ocol o Field Tes ing o
Endu ance Fi ness o Young
Lab ado Re ie e s. Me hods P o oc.
2023,6, 61. h ps://doi.o g/10.3390/
mps6040061
Academic Edi o : Fe nando
Albe icio
Recei ed: 25 May 2023
Re ised: 26 June 2023
Accep ed: 27 June 2023
Published: 28 June 2023
Copy igh : © 2023 by he au ho s.
Licensee MDPI, Basel, Swi ze land.
This a icle is an open access a icle
dis ibu ed unde he e ms and
condi ions o he C ea i e Commons
A ibu ion (CC BY) license (h ps://
c ea i ecommons.o g/licenses/by/
4.0/).
P o ocol
P oposed P o ocol o Field Tes ing o Endu ance Fi ness o
Young Lab ado Re ie e s
Ella-E ika Söde lund 1, Heikki Ky öläinen 2, Ou i M. Lai inen-Vapaa uo i 1and Heli K. Hyy iäinen 1,*
1Depa men o Clinical Equine and Small Animal Medicine, Facul y o Ve e ina y Medicine,
Uni e si y o Helsinki, 00014 Helsinki, Finland; [email p o ec ed] (E.-E.S.);
[email p o ec ed] (O.M.L.-V.)
2Neu omuscula Resea ch Cen e , Facul y o Spo and Heal h Sciences, Uni e si y o Jy äskylä,
40014 Jy äskylä, Finland; [email p o ec ed]
*Co espondence: [email p o ec ed]
Abs ac :
The numbe o dogs and, wi h i , dog spo s a e g owing in popula i y, and he aining o
dogs begins a an ea ly age. Al hough i ness es ing is an impe a i e pa o pu pose ul aining and
spo s, o ou knowledge, no objec i e ield es s a e a ailable o measu ing young dogs’ endu ance
i ness. The aim o his s udy is o desc ibe a simple, easy- o- epea , and inexpensi e way o es
aining in e en ion e ec s on endu ance i ness in young Lab ado Re ie e s. Heal hy clien -
owned 16-week-old Lab ado Re ie e s will be ec ui ed and di ided in o es and con ol g oups.
The es g oup will ha e an eigh -week aining p og am ollowed by a ou -week de aining pe iod,
while he con ol g oup will li e a no mal puppy li e. All dogs will be es ed o endu ance i ness
ou imes a ou -week in e als: a baseline, one mon h la e , wo mon hs la e a he end o he
aining pe iod, and one mon h a e ending he aining p og am. Each o he ou es ing sessions
will be iden ical and will consis o ou measu emen s o hea a e (HR) and blood lac a e (BL):
a baseline, a e o ing 1000 m, a e sp in ing 200 m, and a eco e y 5–8 min a e he sp in .
The aining-induced changes in endu ance i ness a e e alua ed by changes in HR and hea a e
eco e y imes (HRR), BL, and unning imes.
Keywo ds: physical i ness; i ness es ; ae obic i ness; endu ance es ; dog
1. In oduc ion
In humans, physical i ness is de ined by he Ame ican College o Spo Medicine
(ASCM) as “a se o a ibu es o cha ac e is ics ha people ha e o achie e ha ela es o
he abili y o pe o m physical ac i i y” [
1
]. Physical i ness is u he di ided in o skill-
and heal h- ela ed componen s. One o he heal h- ela ed componen s is ca dio espi a o y
endu ance, also known as ae obic i ness o endu ance i ness [
2
]. Endu ance i ness e e s
o he capaci y o he ci cula o y and espi a o y sys ems o adminis e oxygen o skele al
muscles, hus enabling hem o p oduce ene gy du ing physical ac i i y [
3
,
4
]. When he e
is insu icien oxygen a ailable, anae obic p ocesses (glycolysis) occu o allow o ene gy
p oduc ion, and lac ic acid is o med [
5
]. Accumula ion o lac a e leads o acidosis, which
in u n causes muscle a igue, a enua ing muscle ac ions, and o ce p oduc ion [6].
Ae obic aining has been shown o dec ease es ing hea a e (HR) in humans and
ho ses [
7
–
9
]. HR moni o ing is used o assess he e ec i eness o aining p og ams
and he le el o ca dio ascula i ness, as well as o es ima e indi ec maximal oxygen
up ake (VO2max) du ing exe cise and o measu e he in ensi y o physical pe o mance in
humans, ho ses, and dogs [
7
,
10
–
17
]. HR da a can be compiled wi h an elec oca diog am
by auscul a ion a es o wi h wea able HR senso s [
18
]. In ield es s, di e en HR senso
bel s a e used o measu e HR du ing physical pe o mance [
16
,
19
,
20
]. The e a e HR senso s
and senso bel s designed speci ically o ho ses; o example, Pola Elec o Oy (Kempele,
Finland) has de eloped HR senso s sui able o use unde he saddle while iding and a
Me hods P o oc. 2023,6, 61. h ps://doi.o g/10.3390/mps6040061 h ps://www.mdpi.com/jou nal/mps
Me hods P o oc. 2023,6, 61 2 o 10
handheld senso o quick HR moni o ing. To he au ho s’ knowledge, he e a e no HR
senso s designed o dogs, bu Essne e al. [
20
,
21
] ha e alida ed one human HR senso
model in dogs.
In humans and ho ses, hea a e eco e y ime (HRR) has been hough o indica e
changes in i ness le el and aining s a us [
22
–
26
]. In eli e human a hle es, HRR is only
ela ed o ae obic i ness du ing he i s 10–30 s a e pe o mance [
25
]. In non-a hle e
humans, HRR has been ound o dec ease signi ican ly a e 8 weeks o aining bu o
e u n o almos baseline le els a e 2 weeks o de aining [
24
]. Racing ho ses wi h lowe
es ing HR be o e exe cise has been shown o ha e as e HRR [
27
], which, when no ed
a e in e al exe cise, is ela ed o be e ace pe o mance [
26
]. Ne e heless, he e is a
lack o in o ma ion a ailable ega ding dogs’ HRR and i s ela ion o hei pe o mance
capabili ies.
One key ma ke o endu ance i ness in humans is he concen a ion o lac a e in he
blood ela i e o exe cise in ensi y [
2
,
28
,
29
]. Du ing exe cise, he poin whe e he o ma ion
o lac a e exceeds he elimina ion o lac a e om he blood is called he lac a e h eshold o
anae obic h eshold [
2
,
29
]. Physical pe o mance below his poin is conside ed ae obic
exe cise [
2
,
29
]. Analysis o blood lac a e (BL) can also e lec exe cise in ensi y [
2
,
30
].
The e o e, BL analysis is ou inely pe o med in human spo s medicine [
31
]. BL analyses
a e also used in dogs and ho ses [
19
,
32
–
35
]. Fo example, endu ance- ained dogs ha e
signi ican ly lowe BL concen a ions a e long-dis ance unning han un ained dogs [
36
].
Endu ance- ained dogs ha e been ound o each lac a e h eshold a speeds o 13.9 km/h
(
±
2.9 km/h) [
35
]. A po able, minimally in asi e BL measu emen de ice is eadily
a ailable o dogs, and i has been shown o be eliable in measu ing hei BL le els [
37
]. In
his p o ocol, his me hod will be used o young Lab ado Re ie e s.
In addi ion o he abo e-men ioned me hods, endu ance i ness can be es ed in
humans wi h se e al alida ed ield es ba e ies [
38
–
43
]. One o he mos widely used
ield es s is he 20-min shu le un es (20 mSRT) [
39
,
44
]. In his es , he pa icipan s
un a an inc easing pace o 20 m back and o h un il hey can no longe keep up wi h
he demanded speed. This es has been shown o be alid and eliable o measu ing
ca dio espi a o y i ness in bo h adul s and child en [
39
,
43
,
45
–
47
]. The e a e also ime-
limi ed es s, such as he 6-min walking es (6 MWT) and he 12-min unning es [
48
,
49
], in
which a dis ance a eled o e a ce ain pe iod o ime is measu ed. These wo es s a e no
eliable and alid o child en, and hus, 20 mSRT should be used [
50
]. Ano he op ion is
he dis ance-limi ed es , which measu es he ime spen a eling a ce ain dis ance [
48
,
50
].
A dog wi h good physical i ness has a be e capabili y o pe o m i s ask, which also
educes he isk o inju y; hence, he abili y o measu e he dog’s i ness le el is impe a i e.
Wi h he inc easing numbe o pe s and wo king dogs, owne s’ in e es in he well-being o
hei dogs is also on he ise [
51
–
55
]. P o iding i ness- ela ed in o ma ion o dog owne s
can a ec hei dog handling and exe cising habi s and he eby con ibu e o he well-being
o dogs. Mo eo e , he popula i y o dog spo s is g owing, and dogs’ aining begins a
an ea ly age. This may lead o an inc easing a e o musculoskele al inju ies i he dogs’
physics is no app op ia ely es ed and ained.
Field es s o assessing endu ance i ness in dogs a e sca ce. The six MWT is used in
non-heal hy dogs o cha ac e ize he se e i y o espi a o y and ca diac diseases [
6
,
15
,
56
] and
o cha ac e ize golden e ie e muscula dys ophy [
57
]. The same es has been applied o
sea ch-and- escue dogs oo [
58
]. Howe e , he es does no apply o endu ance i ness es ing.
Ano he i ness es o assessing dogs’ physical i ness has been published [
59
], bu his es
does no include an objec i e measu emen o endu ance i ness; ins ead, i concen a es on
a ious aspec s o locomo ion.
Despi e i ness es ing being an impo an pa o pu pose ul aining and spo s in
o he species, he e a e cu en ly no ield es s a ailable o es ing young dogs’ endu ance
i ness. In e e ina y medicine, cu en ield es s o measu ing endu ance i ness a e
designed o ho ses [8,9,16,60].
Me hods P o oc. 2023,6, 61 3 o 10
The aim o his s udy is hus o design a simple, easy- o- epea , and inexpensi e ield
es o measu e he e ec s o a aining in e en ion on endu ance i ness in young dogs.
This p o ocol will no only be use ul o e e ina y medicine p o essionals bu is also sui able
o be used by non-p o essionals (i.e., owne s and dog aine s).
2. P ocedu e
P i a ely-owned Lab ado Re ie e sibling pai s aged 16 weeks wi h no known heal h
issues and wi h a heal hy gene ic backg ound based on he Finnish Kennel Club heal h
eco ds will be ec ui ed. Exclusion c i e ia will be any de ec ed abno mali ies in lameness
assessmen o in he gene al examina ion. These assessmen s will be epea ed a each
es session igh be o e physical pe o mance. In addi ion, he dogs will be unde he
e e ina ian’s supe ision a all imes. All dog owne s will sign a w i en in o med consen
o m be o e pa icipa ing in he s udy. Owne s will be ad ised ha hey may cancel hei
pa icipa ion a any ime. Fu he mo e, he e e ina ian can wi hd aw he dog o any
jus i ied eason (i.e., heal h- ela ed conce ns, owne - ela ed beha io al issues, e c.). In he
e en o wi hd awal, any esea ch da a collec ed up o ha poin will be used. App o al
o he s udy p o ocol will be sough om he Regional S a e Adminis a i e Agency o
Sou he n Finland. The dogs will be di ided in o wo g oups: om each sibling pai , one o
he siblings will be in he aining g oup, and he o he in he con ol g oup. The dogs will
be andomly assigned o hese g oups. The aining g oup will ha e an eigh -week aining
p og am, including exe cises on an unde wa e eadmill and a home exe cise p og am,
and a de aining pe iod o ou weeks a e inishing he aining p og am. The con ol
g oup will li e a no mal puppy li e, i.e., puppy managemen will be conduc ed acco ding
o each indi idual owne ’s p e e ences, wi h no es ic ions o added exe cises ela ed o
esea ch. Bo h g oups will unde go he same ou come measu emen s a he same ime
poin s (desc ibed below), and o bo h g oups, he s udy pe iod will las a o al o 12 weeks.
2.1. S udy P o ocol
The es will be pe o med in an indoo hall wi h a con olled en i onmen and
empe a u e (15–20
◦
C) and on a good, non-slip su ace (Agili y So ex, Lappse , Helsinki,
Finland) o ensu e a s anda dized es ing en i onmen . P io o each es session, he dog
will be aken ou o a calm walk as a wa m-up and o allow i o de eca e and u ina e. The
dog will be allowed o acclima e o i s su oundings o 5–15 min be o e he es ing. The
leng h o he acclima ion will be based on clinical expe ience. The ime o a es session
will emain consis en h oughou he s udy. The measu emen s o he sibling pai will be
conduc ed consecu i ely on he same day.
The es p o ocol is pe o med in he same way each ime (Figu e 1). A clinical
examina ion and lameness e alua ion will be conduc ed p io o e e y es session, igh
be o e pe o mance. Lameness e alua ion will be conduc ed by palpa ion and manipula ion
as well as gai obse a ion o any indica ions o unsoundness. Each o he i ness es
sessions will consis o wo physical pe o mance se s and ou measu emen s o HR and
BL (Figu e 2). The physical pe o mance will be e alua ed by o ing o 1000 m and a
sp in es o 200 m. Du ing he “ o ” phase, a unning o will be u ilized, de ined wi h
a unning gai wi h a suspension phase be ween each diagonal suppo phase. Du ing
o , he dog will be mo ing o wa d wi h ela i e ease a a cons an “jogging” speed.
Du ing he “sp in ” phase, he dog will be conside ed o sp in when i is galloping. Bo h
o a o y and ans e se gallops will be accep ed. Du ing a sp in , he dog will be mo ing
o wa d as as as i seems o be able o do so, wi h he aim o cons an ly inc easing o
main aining he op speed ha i can be mo i a ed o achie e. HR and BL measu emen s
will be aken be o e physical pe o mance es s (baseline, BASE), a e o ing o 1000 m
(POST1), a e sp in ing o 200 m (POST2), and a eco e y (REC) 5–8 min a e he las
un. These measu emen s will ake abou 10 min o comple e. All measu emen s will be
eco ded on he es o m (Supplemen a y Figu e S1).
Me hods P o oc. 2023,6, 61 4 o 10
Me hodsP o oc.2023,6,xFORPEERREVIEW4o 11


a e  o ing o 1000m(POST1),a e sp in ing o 200m(POST2),anda  eco e y(REC)
5–8mina e  helas  un.Thesemeasu emen swill akeabou 10min ocomple e.All
measu emen swillbe eco dedon he es  o m(Supplemen a yFigu eS1).
Figu e1.Thes uc u eo  heendu ance i ness es p ocedu e.Thep ocedu ewillbeca iedou in
hesameway o each es session.HR=hea  a e,BL=bloodlac a e,App=Pola EquineApp.

Figu e2.Thes uc u eo  he i ness es session.Eacho  he i ness es sessionswillconsis o  ou 
measu emen so hea  a e(HR)andbloodlac a e(BL):baselinea  es (BASE),a e  o ing1000
m(POST1),a e sp in ing200m(POST2),and eco e yo 5–8mina e  helas  un(REC).
Runningdis anceswillbemeasu edwi ha ange inde andma kedclea lywi h
cones.Du ing he es , hedogwillwea anon-slipcolla o ha ness,andi willha ewa e 
a ailablea e  he es .Eachdogwilluse hei ownindi idually i ed es ain s(i.e.,ha -
nesso colla andlead).App op ia e i willbecon i medby hepe son esponsible o 
es ing.In hecaseo inapp op ia egea ,anindi iduallyadjus ablecolla willbep o-
idedby he esea ch eam.
The es willbein e up edi  hedogbecomeslameo showsanysignso excessi e
a igue.Signso low-le el a igueinclude, o example,sudden eluc ance omo eo ex-
cessi epan ing[35,37].Signso se e e a igueincludedogsgoingaw yo collapsing
[35,37].As hedogsin hiss udywillbeyoung, he es canno becon inuedun ilse e e
signsa eno iced,bu  he es mus bediscon inueda low-le elsigns.Thesignswillbe
obse edby heowne aswellas he e e ina ianand heassis an (a e e ina ynu se),
all amilia wi h heb eed.
Thedogswill o alongside hei owne o anassis an  o 1000m.I acons an  o 
ismain ained, hespeedo  he o willno becon olled.A e  o ing o 1000m, he
dogwillbes oppedandPOST1measu emen swillbepe o med.Immedia ely,HRwill
be eco ded om hepulsemoni o ’smobileapplica ion(app),andblood om heinne 
Gene al
examina ion
O hopedic
assessmen
Connec ing he HR
senso o App
Placing he HR
senso
Ensu ing he igh
place o HR senso
wi h palpa ion
Con i ming he HR
in he App is
cong uen wi h he
auscul a ion
Measu ing BL
T o ing 1000 m Reco ding o HR
Measu ing BL
Sp in ing 200 m
Reco ding HR Measu ing BL
Res o 5–8 min,
eco ding HR all he
ime
Measu ing BL a e
5–8 min es
Figu e 1.
The s uc u e o he endu ance i ness es p ocedu e. The p ocedu e will be ca ied ou in
he same way o each es session. HR = hea a e, BL = blood lac a e, App = Pola Equine App.
Me hodsP o oc.2023,6,xFORPEERREVIEW4o 11


a e  o ing o 1000m(POST1),a e sp in ing o 200m(POST2),anda  eco e y(REC)
5–8mina e  helas  un.Thesemeasu emen swill akeabou 10min ocomple e.All
measu emen swillbe eco dedon he es  o m(Supplemen a yFigu eS1).
Figu e1.Thes uc u eo  heendu ance i ness es p ocedu e.Thep ocedu ewillbeca iedou in
hesameway o each es session.HR=hea  a e,BL=bloodlac a e,App=Pola EquineApp.

Figu e2.Thes uc u eo  he i ness es session.Eacho  he i ness es sessionswillconsis o  ou 
measu emen so hea  a e(HR)andbloodlac a e(BL):baselinea  es (BASE),a e  o ing1000
m(POST1),a e sp in ing200m(POST2),and eco e yo 5–8mina e  helas  un(REC).
Runningdis anceswillbemeasu edwi ha ange inde andma kedclea lywi h
cones.Du ing he es , hedogwillwea anon-slipcolla o ha ness,andi willha ewa e 
a ailablea e  he es .Eachdogwilluse hei ownindi idually i ed es ain s(i.e.,ha -
nesso colla andlead).App op ia e i willbecon i medby hepe son esponsible o 
es ing.In hecaseo inapp op ia egea ,anindi iduallyadjus ablecolla willbep o-
idedby he esea ch eam.
The es willbein e up edi  hedogbecomeslameo showsanysignso excessi e
a igue.Signso low-le el a igueinclude, o example,sudden eluc ance omo eo ex-
cessi epan ing[35,37].Signso se e e a igueincludedogsgoingaw yo collapsing
[35,37].As hedogsin hiss udywillbeyoung, he es canno becon inuedun ilse e e
signsa eno iced,bu  he es mus bediscon inueda low-le elsigns.Thesignswillbe
obse edby heowne aswellas he e e ina ianand heassis an (a e e ina ynu se),
all amilia wi h heb eed.
Thedogswill o alongside hei owne o anassis an  o 1000m.I acons an  o 
ismain ained, hespeedo  he o willno becon olled.A e  o ing o 1000m, he
dogwillbes oppedandPOST1measu emen swillbepe o med.Immedia ely,HRwill
be eco ded om hepulsemoni o ’smobileapplica ion(app),andblood om heinne 
Gene al
examina ion
O hopedic
assessmen
Connec ing he HR
senso o App
Placing he HR
senso
Ensu ing he igh
place o HR senso
wi h palpa ion
Con i ming he HR
in he App is
cong uen wi h he
auscul a ion
Measu ing BL
T o ing 1000 m Reco ding o HR
Measu ing BL
Sp in ing 200 m
Reco ding HR Measu ing BL
Res o 5–8 min,
eco ding HR all he
ime
Measu ing BL a e
5–8 min es
Figu e 2.
The s uc u e o he i ness es session. Each o he i ness es sessions will consis o ou
measu emen s o hea a e (HR) and blood lac a e (BL): baseline a es (BASE), a e o ing 1000 m
(POST1), a e sp in ing 200 m (POST2), and eco e y o 5–8 min a e he las un (REC).
Running dis ances will be measu ed wi h a ange inde and ma ked clea ly wi h
cones. Du ing he es , he dog will wea a non-slip colla o ha ness, and i will ha e
wa e a ailable a e he es . Each dog will use hei own indi idually i ed es ain s (i.e.,
ha ness o colla and lead). App op ia e i will be con i med by he pe son esponsible o
es ing. In he case o inapp op ia e gea , an indi idually adjus able colla will be p o ided
by he esea ch eam.
The es will be in e up ed i he dog becomes lame o shows any signs o excessi e
a igue. Signs o low-le el a igue include, o example, sudden eluc ance o mo e o excessi e
pan ing [
35
,
37
]. Signs o se e e a igue include dogs going aw y o collapsing [
35
,
37
]. As he
dogs in his s udy will be young, he es canno be con inued un il se e e signs a e no iced,
bu he es mus be discon inued a low-le el signs. The signs will be obse ed by he owne
as well as he e e ina ian and he assis an (a e e ina y nu se), all amilia wi h he b eed.
The dogs will o alongside hei owne o an assis an o 1000 m. I a cons an
o is main ained, he speed o he o will no be con olled. A e o ing o 1000 m,
he dog will be s opped and POST1 measu emen s will be pe o med. Immedia ely, HR
will be eco ded om he pulse moni o ’s mobile applica ion (app), and blood om he
inne side o he ea lap will be d awn o assess he BL le el. HR will also be measu ed
wi h a s e hoscope i he e is suspicion o senso - o-app connec ion ailu e (no ed as an
excep ionally low o high HR o no HR). The es will con inue immedia ely a e he
measu emen s wi h a 200 m sp in , unning as as as possible. A e sp in ing he 200 m,
he dog will again be s opped, and HR and BL measu emen s will be epea ed (POST 2).

Me hods P o oc. 2023,6, 61 5 o 10
Once he POST2 measu emen s a e conduc ed, he dog will be encou aged o lie down
and ha e a es , wi h no s imulus p o ided. This will be accomplished h ough e bal and
non- e bal ins uc ions and he dog’s mo i a ion. The dog needs o lie down as i needs
o calm down and be elaxed. Once he dog is calm, nei he he owne no he esea ch
pe sonnel will speak o i . A e 5–8 min, HR and BL will be measu ed again (REC). The HR
is moni o ed h ough he app so ha he dog will no be dis u bed. HR will be moni o ed
un il i is back o he base alue. The ime aken o achie e he le el o es ing HR will be
eco ded and conside ed HRR. The unning speeds o he 1000 m o and 200 m sp in will
be ob ained om he app.
2.2. Desc ip ion o Measu emen Technique
All he i ness es measu emen s will be conduc ed immedia ely, which means wi hin
a ew seconds a e exe cise. Du ing he measu emen s, an assis an will hold he dog. In
cases o beha io al easons (i.e., a sensi i e dog), he owne can handle he dog. In his case,
owne s will be ins uc ed o handle he dogs in a s anda dized manne o ensu e p ope and
consis en managemen o he dogs h oughou he es and hus o e i y he accep able
epea abili y o he p o ocol. I will be allowed o s and o si bu no o lie down, excep o
he REC measu emen s, when he dog will be encou aged o lie down. The HR o he dog
will be eco ded by auscul a ion wi h a s e hoscope placed on he le side o he dog a he
i h o six h in e cos al space. The hea will be auscul a ed o 15 s. The esul ob ained
will be mul iplied by ou o ob ain bea s pe minu e (bpm). The esul will be e e ed o
as he baseline HR. Auscul a ion will be conduc ed p io o placing he HR senso , which
will be se o he same, abo e-desc ibed place. The HR senso (Pola H10 senso , Pola
Elec o Oy, Kempele, Finland, Ca . No.: 92075957) will be a ached o i s ches s ap. To
imp o e con ac be ween he ches s ap and he skin, he dog’s coa will be wa e ed on
he le side o he dog a he i h o six h in e cos al space, and e e ina y lub ican gel
(K uuse Bo i e Gel, K uuse, Langesko , Denma k) will be applied o he measu emen
a ea o he ches s ap. I will hen be a ached o he dog’s ches . The co ec place o
he HR senso will be con i med by palpa ing he hea h ough he senso . I needed, he
dog is allowed o acclima e o he ches s ap o up o 15 min. P io o a aching he HR
senso o he dog, he senso will be connec ed o an app (Pola Equine app, e sion 1.2.1,
Pola Elec o Oy, Kempele, Finland), which can be downloaded om Google Play (Google
I eland Limi ed, Dublin, I eland) o a sma phone. Fo he app o wo k, he de ice mus be
an And oid phone wi h an ope a ing sys em o 6.0 o newe , and he phone mus be a leas
Blue oo h 4.0 compa ible. The app will display HR in eal- ime, so HR can be moni o ed
om a dis ance wi hou dis u bing he dog. The app will also collec da a on unning speed
and dis ance.
The e ec s o a ious ac ions du ing he es (such as aking blood samples o BL
measu emen s) on he HR can be seen h ough he con inuous collec ion o HR da a. A e
a aching he HR senso o he dog, he applica ion is con i med by auscul a ing he HR
simul aneously.
While he owne o assis an holds he dog, he inne su ace o he dog’s ea lap will
be wiped wi h an an isep ic and allowed o d y o 5–10 s. I he ea lap is s ill we , i can
be wiped wi h a clean, d y gauze. A s e ile 22-gauge needle will be used o make a small
punc u e on he inne su ace o he ea lap. A blood d op will be d awn and applied
immedia ely o a eac an s ip placed on a handheld lac a e analyze (Lac a e Scou 4,
SensLab Gmbh, Leipzig, Ge many, Ca . no.: 7023-0441-0246) o de e mine BL.
3. Expec ed Resul s
The sample size calcula ions will employ esul s o p e iously published simila
s udies [
6
,
15
,
56
–
58
] and equi ed es ima es based on clinical expe ience. A s a is ician
specialized in medical esea ch will be consul ed in he assessmen o he equi ed numbe
o dogs. Powe analysis wi h a leas 80% powe will be used wi h a s a is ical signi icance
le el o p= 0.05.
Me hods P o oc. 2023,6, 61 6 o 10
P ima y ou come a iables o he es p o ocol will be changes in BL, HR, and HRR
induced by an eigh -week aining in e en ion. Changes in hese pa ame e s will be
e alua ed by compa ing measu emen s a baseline, a e he in e en ion, and a e he
de aining pe iod. Main enance o he changes will be assessed by measu ing he pa am-
e e s a he end o he in e en ion and a e a ou -week de aining pe iod. Desc ip i e
s a is ics will be calcula ed o he measu ed HR, BL, and HRR alues. Fo BL, change om
POST2 a REC will also be calcula ed. The s a is ical calcula ions will be pe o med using
SAS so wa e e sion 9.4 (SAS Ins i u e Inc., Ca y, NC, USA).
4. Discussion
Al hough no es s a e a ailable o young dogs, some i ness es s o adul dogs
ha e been published [
58
,
59
,
61
–
63
]. Mos o he published i ness es s a e labo a o y ypes
pe o med on a eadmill, o i hey a e ac ual ield es s, hey do no speci ically measu e
endu ance i ness bu ocus mo e on o e all physical i ness [
58
,
59
]. One s udy has assessed
he eliabili y o a eadmill exe cise es agains BL, HR, and body empe a u e esponses
o inc emen al exe cise in dogs [
61
]. This es o i s modi ica ions ha e been used in o he
s udies measu ing endu ance i ness in dogs [
61
–
63
]. Howe e , eadmills may no be
eadily a ailable o e e yone needing o es dogs’ endu ance i ness. Thus, es s wi hou
eadmills could be mo e easible, al hough hey migh ha e hei challenges. Fo example,
in ou s udy, as he puppies g ow, hei unning speed du ing sp in s migh be oo as o
a human o keep up wi h. The e o e, wi hou a eadmill, he p oposed p o ocol would no
be sui able o adul dogs.
In ou p oposed p o ocol, he dis ances o be o ed and sp in ed a e chosen acco ding
o he bes clinical knowledge om bo h human and e e ina y medicine. In humans, he e
a e no s udies o uni ied opinions abou a sui able unning dis ance o child en. Acco ding
o Finley e al. [
64
], mos o he child en’s c oss-coun y coaches conside a sui able unning
dis ance in compe i ions o 6- o 9-yea -olds o be 800–1600 m. Based on clinical expe ience
and common mu ual unde s anding, a sui able unning dis ance o young dogs is highly
dependen on he b eed, bu a puppy o a non-chond odys ophic b eed should be able o
un o a leas 5 min pe mon h o age, wo imes a day. In ou p o ocol, o ing o 1000 m
ep esen s ae obic pe o mance, and sp in ing o 200 m ep esen s anae obic pe o mance.
A challenge o hese unning dis ances may be ha hey a e oo sho o ele a e a young
dog’s HR and BL.
In humans, nume ic ables a e used in ield es s o quan i y endu ance i -
ness [
48
,
49
,
65
,
66
]. These ables ac o in he ime used o he pe o mance o dis ance
co e ed in a ce ain ime [
48
,
49
,
65
,
66
]. In ho ses, ypically measu ed physical pa ame-
e s in i ness ield es s a e HR, HRR, and BL [
26
,
27
,
67
,
68
]. These also apply o canine
endu ance es s pe o med on a eadmill, wi h he addi ion o body empe a u e as
a ypically measu ed a iable [
36
,
59
,
69
,
70
]. In ou p oposed p o ocol, BL, HR, and
HRR will be used o e alua e he changes in endu ance i ness. We will no use body
empe a u e because wi h young dogs i migh ake oo much ime o measu e be-
ween he ae obic and anae obic pe o mances, gi ing he dogs oo much es be ween
pe o mance se s.
A speci ic HR senso , o iginally designed o humans, has also been alida ed o
dogs [
20
,
21
]. Howe e , his pa icula de ice is no longe a ailable, and he e o e, he Pola
H10 senso will be used in his es . Wi h his HR senso and he Pola Equine app, HR
as well as unning imes and speeds can be measu ed. Possible challenges may be ha
he HR senso bel a ound he dog’s ches can dis u b he dog while unning. Also, i
he dog has a e y hick coa o is e y obese, he con ac o he HR senso bel migh be
insu icien . I possible, hai could be sha ed om he senso a ea, bu his is no obliga o y.
Al hough sha ing hai would imp o e senso con ac , as he dogs included in he s udy
will be p i a ely owned, he decision on clipping he hai is he owne ’s decision. Mo eo e ,
manda o y hai clipping migh a ec he owne ’s willingness o use he HR senso bel
and hus he whole es .
Me hods P o oc. 2023,6, 61 7 o 10
The e a e only a ew HRR- ela ed s udies in animals, and mos o hem ha e been
conduc ed in ho ses [
26
,
27
,
60
]. In his s udy, we will use HRR as a pe o mance indica o
in endu ance es ing because i is a simple, inexpensi e, and non-in asi e me hod. The
beha io o young dogs may a y ma kedly, and i he dog is e y sensi i e, i migh also
ha e an in luence on he HRR.
Fo BL measu emen s, a handheld Lac a e Scou 4 analyze will be used in ou s udy.
Lac a e Scou analyze measu emen s ha e been shown o be compa able wi h labo a o y
me hods [
34
,
37
]. The analyze is simple, po able, and apid, making i ideal o ield use. In
addi ion o he esul s being eadable in 10 s, only a e y small amoun o blood (0.5
µ
L) is
needed o he sample. The analyze also has a wide ange o measu emen s (0.5–25.0 mmol/L)
(14). In he p o ocol p oposed he e, he blood sample will be aken om he inne su ace o he
ea lap, bu i his is no possible, he sample can be aken om he me aca pal pad.
In human medicine, physiological esponses o exe cise a e known o change du ing
g ow h and de elopmen , and hus, pedia ic es s ha e hei own ou come e e ence
alues ins ead o sha ing he adul no ms [
71
,
72
]. The musculoskele al sys em o young
dogs is somewha di e en om ha o an adul dog. The bigges di e ences a e seen in
he unc ions o he hea and ci cula o y sys em. In young dogs, he hea size is la ge in
ela ion o he body weigh han in adul dogs [
73
]. On a e age, g owing dogs ha e lowe
ed blood cell, hemoglobin, and hema oc i alues han adul dogs, which weakens he
anspo o oxygen in he bloods eam [
74
,
75
]. The e o e, he esul s o i ness es s on
young dogs a e no compa able o hose o adul dogs.
To he au ho s’ knowledge, he e a e no published a icles abou i ness es ing in
young dogs. The p oposed p o ocol o ield es ing he endu ance i ness o young dogs is
use ul because he equipmen and en i onmen needed o he es a e inexpensi e and
eadily a ailable, and he p o ocol is non-in asi e.
Supplemen a y Ma e ials:
The ollowing suppo ing in o ma ion can be downloaded a : h ps:
//www.mdpi.com/a icle/10.3390/mps6040061/s1, Supplemen a y Figu e S1, Fo m o use in
eco ding measu emen esul s.
Au ho Con ibu ions:
Concep ualiza ion, E.-E.S., H.K., O.M.L.-V. and H.K.H.; w i ing—o iginal
d a p epa a ion, E.-E.S.; w i ing— e iew and edi ing, E.-E.S., H.K., O.M.L.-V. and H.K.H.; isualiza-
ion, E.-E.S. and H.K.H.; supe ision, H.K., O.M.L.-V. and H.K.H.; p ojec adminis a ion, E.-E.S. and
H.K.H.; unding acquisi ion, H.K.H. All au ho s ha e ead and ag eed o he published e sion o
he manusc ip .
Funding:
This esea ch was unded by he Academy o Finland, g an numbe 315673. Open access
unding p o ided by Uni e si y o Helsinki.
Ins i u ional Re iew Boa d S a emen :
The animal s udy p o ocol was app o ed by he Ins i u ional
Re iew Boa d o Regional S a e Adminis a i e Agency o Sou he n Finland (ESAVI/11887/2019,
da e o app o al 14 May 2019).
In o med Consen S a emen : No applicaple.
Da a A ailabili y S a emen :
No new da a we e c ea ed o analyzed in his s udy. Da a sha ing is
no applicable o his a icle.
Con lic s o In e es :
The au ho s decla e no con lic o in e es . The unde s had no ole in he design
o he s udy; in he collec ion, analyses, o in e p e a ion o da a; in he w i ing o he manusc ip ; o
in he decision o publish he esul s.
Re e ences
1.
Thompson, W.R.; Go don, N.F.; Pesca ello, L.S. Ame ican College o Spo s Medicine. In ACSM’s Guidelines o Exe cise Tes ing and
P esc ip ion, 8 h ed.; Lippinco Williams & Wilkins: Philadelphia, PA, USA, 2010; ISBN 978-0-78817-6903-7.
2.
Jones, A.M.; Ca e , H. The e ec o endu ance aining on pa ame e s o ae obic i ness. Spo s Med.
2000
,29, 373–386. [C ossRe ]
3.
Caspe sen, C.J.; Powell, K.E.; Ch is ensen, G.M. Physical ac i i y, exe cise, and physical i ness: De ini ions and dis inc ions o
heal h- ela ed esea ch. Public Heal h Rep. 1985,100, 126–131.
Me hods P o oc. 2023,6, 61 8 o 10
4.
Ross, R.; Blai , S.N.; A ena, R.; Chu ch, T.S.; Desp és, J.P.; F anklin, B.A.; Haskell, W.L.; Kaminsky, L.A.; Le ine, B.D.; La ie, C.J.;
e al. Ame ican Hea Associa ion Physical Ac i i y Commi ee o he Council on Li es yle and Ca diome abolic Heal h; Council
on Clinical Ca diology; Council on Epidemiology and P e en ion; Council on Ca dio ascula and S oke Nu sing; Council on
Func ional Genomics and T ansla ional Biology; S oke Council. Impo ance o assessing ca dio espi a o y i ness in clinical i al
signs: A scien i ic s a emen om he Ame ican Hea Associa ion. Ci cula ion 2016,134, 653–699. [C ossRe ]
5. Ha g ie es, M.; Sp ie , L.L. Skele al muscle ene gy me abolism du ing exe cise. Na . Me ab. 2020,2, 817–823. [C ossRe ]
6.
Hogan, M.C.; Gladden, L.B.; Ku dak, S.S.; Poole, D.C. Inc eased [lac a e] in wo king dog muscle educes ension de elopmen
independen o pH. Med. Sci. Spo s Exe c. 1995,27, 371–377. [C ossRe ]
7.
Co nelissen, V.A.; Ve heyden, B.; Aube , A.E.; Faga d, R.H. E ec s o ae obic aining in ensi y on es ing, exe cise and
pos -exe cise blood p essu e, hea a e and hea - a e a iabili y. J. Hum. Hype ens. 2010,24, 175–182. [C ossRe ]
8.
Kuwaha a, M.; Hi aga, A.; Kai, M.; Tsubone, H.; Sugano, S. In luence o aining on au onomic ne ous unc ion in ho ses:
E alua ion by powe spec al analysis o hea a e a iabili y. Equine Ve . J. Suppl. 1999,30, 178–180. [C ossRe ]
9.
Be os, C.L.; McKee e , N.M.; Manso Filho, H.C.; Malinowski, K.; McKee e , K.H. E ec o aining on in insic and es ing hea
a e and plasma olume inn young and old ho ses. Comp. Exe c. Physiol. 2013,9, 43–50. [C ossRe ]
10.
Wagne , J.A.; Ho a h, S.M.; Dahms, T.E. Ca dio ascula , espi a o y, and me abolic adjus men s o exe cise in dogs. J. Appl.
Physiol. Respi . En i on. Exe c. Physiol. 1977,42, 403–407. [C ossRe ]
11. Mo gan, K.; Hughes, A.O.; Philipp, R. Reliabili y o a es o ca dio ascula i ness. In . J. Epidemiol. 1984,13, 32–37. [C ossRe ]
12.
T eibe , F.A.; Musan e, L.; Ha dagan, S.; Da is, H.; Le y, M.; S ong, W.B. Valida ion o a hea a e moni o wi h child en in
labo a o y and ield se ings. Med. Sci. Spo s Exe c. 1989,21, 338–342. [C ossRe ]
13.
Boddy, K.N.; Roche, B.M.; Schwa z, D.S.; Nakayama, T.; Hamlin, R.I. E alua ion o he six-minu e walk es in dogs. Am. J. Ve .
Res. 2004,65, 311–333. [C ossRe ]
14.
Fe asin, L.; Ma co a, S. A pilo s udy o assess he easibili y o a submaximal exe cise es o measu e indi idual esponse o
ca diac medica ion in dogs wi h acqui ed hea ailu e. Ve . Res. Commun. 2007,31, 725–737. [C ossRe ]
15.
Swimme , R.A.; Rozanski, E.A. E alua ion o he 6 minu e walk es (6MWT) in pe dogs. J. Ve . In e n. Med.
2011
,25, 405–406.
[C ossRe ]
16.
Coelho, C.S.; Adam, G.L.; Ag a de Omena E Sil a, G.; Sil a de Ca alho, R.; Cuña de Souza, V.R.; Fazio, F. Hea a e moni o ing
in Mangala ga Ma chado ho ses du ing a ield ma cha Tes . J. Equine Ve . Sci. 2019,79, 50–53. [C ossRe ]
17.
Salie E iksson, J.; Olsson, K.S.E.; Rosdahl, H.; Schan z, P. Hea a e me hods can be alid o es ima ing in ensi y spec ums o
oxygen up ake in ield exe cise. F on . Physiol. 2021,112, 345–355. [C ossRe ]
18.
Shull, S.A.; Rich, S.K.; Gille e, R.L.; Man edi, J.M. Hea Ra e Changes Be o e, Du ing, and A e T eadmill Walking Exe cise in
No mal Dogs. F on . Ve . Sci. 2021,8, 641871. [C ossRe ]
19.
Muñoz, A.; Ribe , C.; San is eban, R.; Rubio, M.D.; Agüe a, E.I.; Cas ejón, F.M. Ca dio ascula and me abolic adap a ions in
ho ses compe ing in c oss-coun y e en s. J. Ve . Med. Sci. 1999,61, 13–20. [C ossRe ]
20.
Essne , A.; Sjös öm, R.; Ahlg en, E.; Lindma k, B. Validi y and eliabili y o Pola
®
RS800CX hea a e moni o , measu ing hea
a e in dogs du ing s anding posi ion and a o on a eadmill. Physiol. Beha . 2013,114, 1–5. [C ossRe ]
21.
Essne , A.; Sjös öm, R.; Ahlg en, E.; Gus ås, P.; Edge-Hughes, L.; Ze e be g, L.; Hells öm, K. Compa ison o Pola
®
RS800CX
hea a e moni o and elec oca diog am o measu ing in e -bea in e als in heal hy dogs. Physiol. Beha .
2015
,138, 247–253.
[C ossRe ]
22. Bunc, V.; Helle , J.; Leso, J. Kine ics o hea a e esponses o exe cise. J. Spo s Sci. 1988,6, 39–48. [C ossRe ]
23. Sho , K.R.; Sedlock, D.A. Excess pos exe cise oxygen consump ion and eco e y a e in ained and un ained subjec s. J. Appl.
Physiol. 1985,83, 153–159. [C ossRe ]
24.
Sugawa a, J.; Mu akami, H.; Maeda, S.; Kuno, S.; Ma suda, M. Change in pos -exe cise agal eac i a ion wi h exe cise aining
and de aining in young men. Eu . J. Appl. Physiol. 2001,85, 259–263. [C ossRe ]
25.
Wa son, A.M.; B ickson, S.L.; P awda, E.R.; San ilippo, J.L. Sho - e m hea a e eco e y is ela ed o ae obic i ness in eli e
in e mi en spo a hle es. J. S eng h Cond. Res. 2017,31, 1055–1061. [C ossRe ]
26.
Wilson, G.; McGowan, C.M. Reco e y hea a es as a p edic o o ace posi ion in ace- i na ional hun aceho ses. Comp. Exe c.
Physiol. 2019,12, 307–312. [C ossRe ]
27.
Lindne , A.; Esse , M.; López, R.; Bo i, F. Rela ionship be ween es ing and eco e y hea a e in ho ses. Animals
2020
,10, 120.
[C ossRe ]
28.
Londe ee, B.R. E ec o aining on lac a e/ en ila o y h esholds: A me a-analysis. Med. Sci. Spo s Exe c.
1997
,29, 837–843.
[C ossRe ]
29.
Heube ge , J.A.A.C.; Gal, P.; S uu man, F.E.; de Muinck Keize , W.A.S.; Mejia Mi anda, Y.; Cohen, A.F. Repea abili y and p edic i e
alue o lac a e h eshold concep s in endu ance spo s. PLoS ONE 2018,13, e0206846. [C ossRe ]
30.
Ben ley, D.J.; McNaugh on, L.R.; Thompson, D.; Vleck, V.E.; Ba e ham, A.M. Peak powe ou pu , he lac a e h eshold, and ime
ial pe o mance in cyclis s. Med. Sci. Spo s Exe c. 2001,33, 2077–2081. [C ossRe ]
31.
Tanne , R.K.; Fulle , K.L.; Ross, M.L. E alua ion o h ee po able blood lac a e analyse s: Lac a e P o, Lac a e Scou and Lac a e
Plus. Eu . J. Appl. Physiol. 2010,109, 551–559. [C ossRe ]
32.
E ans, D.L.; Rainge , J.E.; Hodgson, D.R.; Ea on, M.D.; Rose, R.J. The e ec s o in ensi y and du a ion o aining on blood lac a e
concen a ions du ing and a e exe cise. Eq. Ve . J. 1995,18, 422–425. [C ossRe ]